Is PVC Safe for Aquaponics and Hydroponics?

More and more individuals are turning toward growing their foods. Since the limited amount of space some people have, they seek alternative and inventive ways to grow vegetables. With this, came the advent of hydroponics and also a fork of this we know as aquaponics.

Many of these systems will be based around piping and tubing to transfer water. It is possible to purchase made for purpose pipes and tubes, yet the DIY nature of many system builders is they turn toward PVC pipes and tubes. You find these components are readily available and highly affordable. However, it does lead to one question.

Is PVC safe for Aquaponics and Hydroponics? There are various standards of PVC, and some are not suitable for either hydroponics or aquaponics. However, there are standards which can deem some PVC as food safe. Before you build your system, it is good to understand the types of PV and the concerns some individuals have.

What Are the Types of PVC?

Here is an overview of the various strains of PVC.

Plain PVC

You will find this in two forms. You have one which is an unplasticized polymer (uPVC) and a flexible plastic.

In the unplasticized form (uPVC), the PVC is rigid and stiff; you will find these two traits make this PVC highly-durable when you compare this to your regular PVC which is much softer, pliable and flexible and also not as durable.


CPVC is a chlorinated type of PVC which offers some unique properties. It provides high glass transition temperature, chemical inertness and high heat distortion temperatures. You often find this in use for mechanical, smoke-related scenarios and dielectric. From the name, you can see it contains a higher degree of chlorine than regular PVC.


This variant of PVC is incredibly tough and possesses vast amounts of impact strength.


Out of all, PVC-O is the strongest and offers very high tensile strength. It is often used in applications where this strength will be a benefit.

Are PVC Pipes Toxic?

The main types of PVC you may use for your systems will be PVC or uPVC, and it is here where the concerns lie.

Instead of thinking, PVC is flexible, while uPVC is rigid. You will find more to it because there are reasons this occurs. When there are no plasticizers added, you end up with a rigid product, and thus it takes on the term of Foods Safe PVC.

Food Safe PVC doesn’t have any Bisphenol A (BPA) or Phthalates, and the lack of these make it safe for use in gardening, regardless of the type. If you are unsure, what you need to be aware of is any mark or stamp that shows the PVC is to NSF-51 rating, and thus, safe for food production.

NSF or National Sanitation Foundation is the organization that does all the testing and sets the standards for public health and environmental safety.

Once your PVC has this NSF-51 rating, you know it meets all the set standards for ‘Plastic Material and Components used in Food Equipment.’

Why is Regular PVC Not Safe for Hydroponics?

While you can see standards that are in place and why uPVC is safe, you ought to understand why regular PVC isn’t food safe and shouldn’t be used in your Hydroponics or Aquaponics gardens.

PVC (Poly Vinyl Chloride) is a thermoplastic polymer they make from various chemicals, which can comprise of Phthalates, Lead and Cadmium. You will find all of these are toxic to humans.

Besides the toxicity of these compounds, when you burn PVC, it gives off a dangerous chemical named Dioxin, and which is a class 1 carcinogenic.

What makes things worse is you cannot recycle PVC pipe. When it faces exposure to sunlight for extended periods, it can pass lead ash through the pipe.

Because PVC has been around for a large number of years, there are landfills and gardens, which are full of PVC pipes breaking down under the force of the sun to create a health hazard to humans.

Even if you are using uPVC in your system and it has exposure to the sun in your hydroponic or aquaponic garden, it may be wise to cover these pipes in some reflective paint or cover. If nothing else, it can help to keep your hydroponic reservoir cooler, which is a good thing.

Gluing PVC Pipes in Hydroponic Systems

With the NSF-51 rating, and the NSF-61 rating determining your PVC pipes are food and water safe. Even if regular PVC is safe if it is out of sight, there is one area which you can find isn’t typically mentioned.

When gardeners build their systems, they may need to glue certain connections. While it is preferable to leave them as a pressure fit, it isn’t always possible to do so.

The problem of over gluing comes into play. Much of the thought goes into the safety and toxicity of PVC, yet the chemical cement is highly toxic. You can obtain a good idea from the smell it gives off, and the feelings of dizziness or you find it hard to breathe if you are in an enclosed area.

PVC cement shouldn’t end up on the skin, and you should never inhale the fumes if possible. When used correctly, there isn’t too much of an issue; it dries quickly and takes you seconds to apply it.

The issue comes from applying too much glue, and when this happens, it can pass into the water. If this were to occur in a hydroponics system, you could clog your pump, yet in aquaponics, it could cause harm to your fish.

What are the Other Types of Plastics?

If you counted the types of plastics in production, you could reach numbers in the thousands. However, here is a handful you may be more familiar with. The FDA sets higher standards for any plastic that will come into contact with anything to do with food or beverages.

  • PET or PETE: Polyethylene terephthalate falls as number 1 in the recycling triangle diagram. It is a clear, strong plastic you will see in use with plastic bottles of water, juice, soda, and peanut butter and spreads. You will find it comes in varying degrees of thickness.
  • HDPE: High-density polyethylene sits in second place in the triangle as is often used for your milk and juice containers as well as some laundry products. You find this plastic thicker than PET and can be clear or colored.
  • PVC: Polyvinyl chloride as we see is best left to what it was designed for, although it can be sued in food production. It is, however, essential to be sure it hasn’t been treated for use in industry.
  • LDPE: Low-density polyethylene plastic is most typically seen in use as bags for frozen foods, bread bags and squeezy bottles.
  • PP: Polypropylene is the one we may see quite often in yogurt or margarine containers and medicine bottles.
  • PS: Polystyrene, is a foam, yet still a plastic. You’ll see PS in plastic plates, cups, cutlery, egg cartons, and meat trays depending on the grade it is made to.
  • Other: Number 7 on the triangle code can be a mix of the above materials or resins not listed. Being food safe, you can find it in use for 5-gallon water bottles, citrus juice bottles, and others.


When building a system, or adding to it, if you choose your PVC safely and make sure it comes with an NSF-51 rating, then you shouldn’t have issues. Keep it out of the sun and try not to use glue, and you will be well on your way to healthy veggies without any worry.

Are Jiffy Pellets Good for Hydroponics?

There is no secret that hydroponic growers are always out to find the best products and techniques to get the most vigorous growth and best yields possible. Because of this mentality, many skip seeds and use seedlings to save time.

When transplanting, there are many options available, peat pellets, Rockwool, coco coir and others. One new kid on the block is the Jiffy Pellets, and for new gardeners, they can be the most straightforward way to get your seeds going.

However, the question remains, because there is a debate on these small plugs.

Are Jiffy Pellets good for hydroponics? Many gardeners say they should use no peat moss in hydroponics when starting seedlings. Once these break down, they end up in your reservoir and can clog your pump. Jiffy Pellets are in mesh, so are these starters any different?

What are Jiffy Pellets?

You will find Jiffy pellets sold as small dry disks. When you add water to the dry peat moss, they will expand. Because of this, and to stop them breaking apart. It contains all the peat or substrate in a fine mesh. This acts as a pot around the material.

You insert your seed in the top and press it into the potting mix. As the seed germinates and roots grow, they arrive at the mesh. Depending on the plant, some roots find the mesh a barrier and remain inside.

Other roots may push through the holes, although as there are no external growing media, they will be root pruned.

Once seedlings are ready, they can be transplanted. All you need to do is drop the Jiffy into a hole and start feeding it.

While very convenient, because they don’t need other pots and potting mixes, and they take up very little space. They are more expensive than a traditional pot and growing media.

Besides this, there are concerns about your plant health, the environment, and if they are actually suitable for hydroponics.

Why I Shouldn’t Use Jiffy Pellets

Hydroponics is a soilless gardening system, and from the seeds to the plants, it is the gardener’s job to deliver the right amount of nutrient solution for their growing needs. Add in lighting, temperature and moisture, and you can find this control just can’t be achieved in soil.

To pass water around your system, you need a water pump, and here is where the debate starts. They make Jiffy Pellets from peat, and as soon as you add water to the flat disks, they expand. Over time the peat eventually breaks down, it can work loose from the mesh and find its way into your system to be flushed to your reservoir, where it clogs your pump.

You will find alternatives like Rockwool or coco coir, or a similar growth media is best for seedlings in hydroponics.

You find that because of the potential pump issues, peat pellets are perfect for seedlings, which you will eventually transplant to soil.

They prove Rockwool and coco coir ideal as growing mediums as they retain water and allow oxygen in the right amounts. Aside from this, they are less likely to break down and clog your pump.

Peat Pots and Environmental Concerns

Jiffy Pellets has claims of biodegradability, and have labels as being composed of natural materials. You will expect the pellets to lose their tidy packaging mesh when it merges with the surrounding soil.

However, there is one thing to note, and that is the lack of given time frame the mesh material is given before it decomposes.

Many gardeners take up the role of growers as they become more environmentally conscious and wish to change their lifestyle to a greener and more efficient manner.

With Jiffy pellets, there are concerns of the biodegradability of the mesh, because there are reports from regular soil gardeners, they don’t decompose as people expect. Even after two years in soil, the Jiffy Pellet mesh is mostly intact, aside from tears where roots work their way out.

Are Jiffy Pellets Good to Use in Hydroponics?

You can find some reports that gardeners do use Jiffy Pellets in hydroponics, yet they place these inside mesh pots to make sure they can sit in their system.

There are reasons Jiffy Pellets shouldn’t be used in your hydroponic system.

Mesh & Roots

If you were to use these pellets in your hydroponic system, you wouldn’t be able to do so as they are. Many plants become rootbound inside the mesh, and you will find stunted growth of your crops. The way around this is to remove the mesh and then remove the peat from around your plant’s roots.

To do this for multiple plants is time consuming and you can cause stress or damage to your plant roots as you rinse them in water to clear away the peat. You then have to dispose of the mesh separately.


The consensus between growers is not to use peat or any similar growing media inside a hydroponic system. As your solution flows, you can find the peat accumulates inside your system as it tangles with roots to cause a blockage, or worse, it finds its way back to your reservoir and blocks your water pump.

Should this happen, all your crops can be at risk of not receiving water and nutrients.


Jiffy pellets comprise peat moss as their primary material. While this offers lots in the way of nutrients, many individuals are unaware of the ecological concerns of using peat moss for anything.

Peat moss doesn’t have an infinite supply. Around the world, there are only so many areas where peat moss can be located, and the mining of this occurs much faster than nature can produce it. A peat bog may only grow by 0.02 inches per year.

Mining of the peat is another factor. Peat holds carbon that will be released into the atmosphere when mined, and it continues to do so long after mining ceases.

The miners also need to drain the water from the bogs, and by doing so, this can have a severe impact on the surrounding water table. Such is the effect, peat is becoming less of a primary growing media in any form of gardening, and alternatives are being sought.

Best Jiffy Pellet Alternative

The drawbacks of using Jiffy pellets should be sufficient for any gardener to see they shouldn’t be used. Because of this, indoor gardeners seek alternatives, and one of the best is coco coir pellets. While there is still a manufacturing process, the fibers used to make these pellets were once a waste product in the coconut harvesting industry.

Coco coir has many benefits going for its use. It has fantastic water retention properties, and there is sufficient space in the fibers for rapid root growth and oxygenation. As an aside, you can find insects are not keen on settling in this media.

Coco coir is also reusable depending on how you use it in your system; all it takes is cleaning and sterilization before it’s ready to use again. One downside at present being it is still more expensive than peat to use.


Jiffy Pellets are convenient to use, yet they are more geared to seed germination than cloning. Many hydroponic growers prefer to use cloning as their preferred method of introducing plants into their system.

With this, there are few reasons you need to opt for using Jiffy Plugs in your system as they don’t offer any advantage over other forms of media for cloning.

Last, you can also do your bit by not using them and preserving an extra minor part of the natural environment.

Can You Use Rockwool Insulation for Hydroponics?

Some of the growing media used in hydroponics can become expensive. Because of this, gardeners are always on the lookout for alternatives. One of the most popular growing media you can choose is Rockwool, which is a man-made product where they take rock and sand and heat it to extreme temperatures before they sin it into fibers.

The end product is very similar to the slabs of Rockwool insulation often used in the construction of homes. With this, many gardeners wonder.

Can you use Rockwool insulation for hydroponics? On face value, there is little to distinguish between the two materials. They look and feel the same; however, the differences come with the treatments applied to the insulation. We can use it for hydroponics with some care, but it may not be as effective.

Why Consider Rockwool Insulation?

You may wonder why growers even consider using the insulation rather than the Rockwool, which is made for hydroponics.

A couple of reasons being price and availability. You can find Rockwool insulation at most hardware stores, while hydroponic Rockwool you may need to order online.

Rockwool Insulation Vs. Hydroponic Rockwool

Before thinking you can use the Rockwool with no effect, it is better to understand what the differences are. It would not be very smart to find you have changed your growing media to see your plants suffer without checking what impact a new growing media could have.

Added Chemicals in Rockwool Insulation

Some of the fundamental differences between the two forms of Rockwool are the chemical additives there are. You find these are added to the insulation to make it fireproof and safe to use in your home.

While making them safe for home use, the accumulation of these chemicals over your plant’s life can have a detrimental effect.

Here are two of the compounds added that can affect the growth of your crops.


Using asbestos in Rockwool insulation has been on a decline since they found it led to cancer. They banned the asbestos material from most products during the 80s. However, you can find traces of it in old homes around the country.

When using insulation Rockwool, you can see plants have reduced levels of nutrients in leaves and can suffer from stunted growth as a result.

For humans, there can be irritation of the skin and throat if you breathe in the microscopic fibers. Hence, if you do use this, you need protection if the material is dry.


In manufacture, the addition of Formaldehyde is to act as a binder. However, by the end of the production cycle, they remove most of this chemical, though there are still some traces remaining.

The issue here is if you are using blocks of insulation Rockwool to grow numerous plants, then the levels of Formaldehyde in your system can increase. The effects of this chemical on plant growth are around a 27% decrease in the wet weight of a plant. Also, the water content of your crops can decrease by around 5% per plant.

In use, there is the side affects you may face, from eye, nose and throat irritation through excessive exposure to your insulation Rockwool.

Plant Growth Using Insulation Rockwool

One of the visual differences you may notice if you hold the two compounds next to each other is how much more compressed insulation Rockwool appears to be. Because of this, the roots of your seedlings may struggle to spread in their early days.

As a result, you may see a limited amount of growth from your crops in comparison. Some tests also show that several seeds may not make it past the germination stage when using this material.

If you wish to proceed with this material, you need to prepare it first before you carry on using it.

Treatment of Insulation Rockwool Before Use

If you want to use the material, or you don’t have a choice at that moment, here are the preparation steps you need to follow to negate the adverse side effects of using this material.

While you need to go through these steps of preparation, you need to know that the structure will change, and the insulation Rockwool won’t return the same form as it was before treatment.

1# Washing the insulation

The best way to remove chemicals from the insulation is soak the material in a solution of water and dishwasher detergent, for around 24-hours.

2# Sterilization

You often use this step when reusing your Rockwool blocks again. With the use of Hydrogen Peroxide, you can sterilize your insulation and remove any disease or traces of infectious impurities.

3# Soaking

Rockwool has excellent water retention properties; however, the insulation variety doesn’t offer as much as the Hydroponic Rockwool.

With both types, you need to first soak your material in water until no air bubbles come from the water surface. Once there are no bubbles, you are guaranteed moisture reaching your seeds, seedlings or plants if using 4-inch blocks.

4# Adjusting pH Levels

Rockwool has a higher pH (7.8) than other growing media, so you have to bring this back in line, so it favors your crops. If you don’t do this, then you can affect the pH of your nutrient solution.

If you are using the insulation for germination or seedlings, they won’t be in your system, and you may not yet be using any nutrient solution to feed them. You can soak your cubes in pH adjusted solution to bring it in line during these stages.

Cutting Rockwool Insulation

One area rarely talked about when using insulation Rockwool is not the preparation above, yet the preparation to sit your plants in the blocks.

Hydroponic Rockwool comes in cubes of various sizes and can be from starter plugs to larger cubes to use in flood and drain systems. The larger cubes have an out paper covering to help keep the material in shape.

Aside from this, the starter plugs and the cubes mainly come with pre-cut holes. When deciding to use Rockwool insulation, you will need to do this yourself.

Here’s a quick guide on how to prepare your insulation by cutting the Rockwool. You will need to make sure you soak your insulation to prevent exposure to dust and fibers.

  1. Remove your insulation from the water and place it on several sheets of newspaper.
  2. Gently press the top of your cubes or slab to remove some water.
  3. If you have a slab, try to mark out your blocks and cut these to shape with a sharp knife or scissors.
  4. Mark out and cut two diagonal lines from corner to corner of your blocks.
  5. Take your sharp knife and cut through your blocks about 1/2-inch in depth.
  6. Because you won’t have holes to drop the starter cube into, the way you use your insulation is peeling back the four corners in the center of your block.
  7. Insert your starter cube and push the corners back.


One thing to note is that insulation Rockwool doesn’t possess anywhere near the same water retention properties of Hydroponic Rockwool. When you compare, you may even say it repels water.

While there are a few differences in the manufacture, composure and the way it works in a hydroponic system, it is possible to use insulation as a replacement for hydroponic Rockwool.

The primary question is if you want to go through all the effort to use a cheaper material, yet can be harmful to yourself, your plants and the environment?

Rockwool may be one of the best growing mediums for hydroponics, yet you can find many alternatives that are just as good, and coco coir being a quick example.

Can Cereals be Grown Hydroponically?

With many countries looking to solve food shortages, hydroponics has been seen as another way to maximize crop output without using more arable land, which is diminishing each year.

The main staple crops in many countries are wheat, oats, barley, rice and others. This leads to the question, “Can cereals be grown hydroponically?”

The answer to this isn’t as clear-cut as yes or no. With a carefully built hydroponic system, almost any crop can be grown, yet there some plants, which by their very nature are not designed to grow in hydroponic systems, and others which take more effort than the gain form their yields.

Here we will look to see if this question has an answer one way or the other.

What Can You Grow in Hydroponic Systems?

Many growers have systems inside their homes and make use of growing lights. However, there are also gardeners that are lucky enough to have enough space and can utilize a greenhouse to be the home to their system.

This means they can make use of the sun during the day, and then use grow light as an artificial supplement to the natural light.

Greenhouses can offer a gardener more room, yet these can quickly be outgrown with the wrong crops. When you use a greenhouse, you can see larger yields and it is these, which causes the issues.

Some crops, which are ideal for hydroponic growing, are:

Tomatoes: These thrive if grown in a hydroponic system. Depending on the variety, they will need support for their vines. This is the same if you were growing cucumbers, peas and beans.

Strawberries: These are another great crop to grow in hydroponic systems; however, they can be hard for new growers. There are many varieties, some vine while others are bush growers.

Herbs: Many herbs can be grown and take up very little space.

Leafy greens: Lettuce, kale and many other crops are ideal for growing in a system. These shallow rooting plants thrive in these growing conditions, and it is these, which began the hydroponic boom.

Many other vegetables are suitable for hydroponic growing. These can grow throughout the year, so the chances of fresh food all the time is a distinct possibility. Many smaller plants will grow faster than larger ones and take up less resources and effort.

What Not to Grow in Hydroponic Systems

Even though there are many plants, which are shallow rooted and perfect for hydroponics, there are as many, which are not suitable. These can be for differing reasons.

The first category of plants are those that don’t grow very well in a hydroponic system. Potatoes, yams, sweet potatoes, onions, garlic, carrots and turnips will all thrive better in soil grown condition than in a hydroponic system.

Even if you are a gardener who has a greenhouse, there are still crops that can outgrow these spaces. Squash, melons and many other crops that grow across the ground are not suitable because of the space they take up. These can be grown in hydroponics, yet you will need plenty of space, and then the crops grown per square foot ratio will plummet.

There are a few vining plants that are not suitable for home growers. Depending on the variety, tomatoes and cucumbers can fall into these groups. With trellising and the amount of space needed, they can overwhelm a gardeners growing space.

Adding to this, these large vining plants can drain systems of nutrients, and finally, there will be a continual need for grow lights to be adjusted as the plants grow along their vines. The extra work required can make these plants more effort than the gains that can be achieved.

Plants Which Don’t Make Economic Sense

There are many crops, which don’t make economic sense to farmers and their hydroponic system. Cereals fall into this category although there is a way where growing some cereals can make sense. This we will see later.

If you take wheat as the example, this is one of the most widely consumed cereals around the world. While not being genetically suited to hydroponic growth, there is the factor of the amount of electricity required to grow it.

To grow enough wheat to make a loaf of bread can cost upward of $20 if it was in a warehouse setting. Add to this the amount of space that is needed to grow enough wheat germ to make this loaf. There is no real feasibility for doing so.

Hydroponics is about saving space while growing more. In contradiction, wheat would take more space to grow a sufficient amount of crop, which is any use.

To break this down into a scale that is easier to relate to for a small garden, if you were to have nine square feet of growing area, this would produce around 4 cups of wheat for every harvest. This equates to making a loaf of bread every five months or so.

While this may write off the chances of growing cereals using hydroponic methods, there are ways where hydroponics can be used for cereal production.

Cereals and Hydroponic Water Purification

The American Journal of Agricultural and Biological Science carried out a study back in 2008. While this wasn’t solely about growing wheat, barley or oats hydroponically, it was about using aquaculture wastewater.

This is dependent on the size of garden, and will be geared more too commercial ventures. Taking the wastewater from system flushing can be used for irrigation of these cereal crops. The study showed the seeds were germinated in a hydroponic system where they then received the wastewater from the aquaculture system.

The resulting crops grew faster and didn’t show any sign of mineral deficiency. They did lack any significant amounts of protein, and even for fish food, they would need a supplement to correct this.

Although this isn’t essential growing cereals in a hydroponic system, it does show they are not adverse to absorbing hydroponic nutrients, so the possibility is there is other factors are ideal.

Hydroponic Cereal Sprouts and Microgreens

Sprouts and microgreens are taking the world by storm. These are highly nutritious and tasty. One of the ones which is touted as being a wonder food is “Wheatgrass.”

This is the first few inches of wheat as it begins its growth. Growing wheat or other cereals to maturity may not be cost effective, yet when you grow them to this stage only, they make a lot of economic sense.

You may see wheatgrass around in juice bars or health food stores. It comes with lots of possible health benefits and can be harvested in around 7-10 days.

Any cereal which is grown in this way will be packed full of nutrients and antioxidants. These can be used to help fight inflammation, diabetes and many other ailments.

Most of these can be grown with a weakened nutrient solution in coco coir while stacked on shelves with a grow light above them. They may take minimal watering, yet they still need all the same elements as the rest of a hydroponic garden such as temperature, ventilation and light.

A grower who ventures down this road may be surprised how much demand there is for this kind of small crop. Microgreens are in high demand from restaurants to the health conscious, even if the garden isn’t a commercial venture, it can lead that way, or just deliver many healthy things to spice up the dinner table.


Asking the question of whether or not cereals can be grown hydroponically does leave plenty open to debate. The reasons for not growing wheat is more down to the sense of doing so rather than it can’t be grown to a mature plant hydroponically.

Once you look at sprouts and microgreens, nearly all cereals can be sprouted or grown to a certain age that makes the minimal effort of doing this well worth it for every grower. This way, you can grow more crops in a smaller space and faster than plants reaching maturity.

A defining answer for growing cereals would be yes, but just not in the ways, you expect plants to grow. As you can see above, at the current time, there are many other crops that can be grown in hydroponic systems, yet the ways systems are set up, they are not a viable crop to do so.

Be it for growing constraints or the economic side rules them out, it doesn’t mean they can’t be grown using these methods.

Why Do Hydroponics Need Flushing?

New growers will often become confused when flushing is spoken about. It isn’t so much how to flush that becomes confusing, it is the “Why do hydroponics need Flushing?” which can catch them out. One of the first reasons is purely and simple as a means of maintaining system cleanliness.

The second is a little more in depth because it occurs at a different time, and for a very specific reason.

Here we will look at both kinds of system flushing, why there is a difference between flushing a system after a harvest as opposed to before a harvest, and how you can flush systems quickly and easily.

In a quick summary, here is what routine flushing of systems can help with:

  • Removes excess of salts and harsh compounds
  • Ensures a balance of nutrients
  • Allows you the opportunity to clean a system
  • Restoring crop growth in dying plants
  • Leading to better growth and flavor

Flushing Plants for Maximum Yields and Flavor

This can be the area that confuses new growers, and can cause them to make mistakes which affects the final growth of their plants and crops.

Flushing before a harvest doesn’t need to be complicated, and it doesn’t matter what brand of nutrient mixes you use, it can still offer you many benefits.

Why flush before a harvest?

What growers may not understand is that flushing systems before harvest is an easy method of increasing the final crop quality, to top this, it is free to do.

The reason this helps is, the process plants go through in the vegetative phase where they absorb the nutrients can actually cause them to have a buildup of salts or other compounds, which are not beneficial.

If these are left in the system during harvest phases, it can lead to a compromise in the outcome of the crops. This final flushing has some potential benefits like reducing harshness of the product and removing traces of chemical taste from crops.

This leads to a final improvement in overall plant quality as the plants are not wasting any energy to absorb nutrients as they would usually.

When and Why to flush before harvests?

It does take some consideration when to begin flushing before a harvest as it can have repercussions. If you do this too early, you won’t be just removing these excesses, you will start to deprive your crops of nutrients and leave yourself with nutrient deficiencies.

Growing medium in use can also make a difference. DWC growers can have the shortest flushing time as whatever they do will have an immediate effect. If using coco coir, then this can have the longest flushing time because the medium retains a high level of nutrients.

The ultimate goal is to rid your plants from the excess salts, however, when you use plain water, you are relying on this to cleanse your plant, growing medium and root system of these salts. You are actually starting to starve plants right before a harvest. While this may sound counterproductive, it does force the plants to use any excess nutrients they have in their system.

It is here where plants take on a more natural flavor and smell. There are solutions you can purchase which contain chelates. These can remove the harmful residues from all the areas of plants and systems, as they contain a broad type of chelates for this purpose. End results of crops can be bountiful and these solutions are shown to be effective, yet some can cause shock to plants.

Flushing to Correct Nutrient Lockout and System Cleans

While we have this kind of flushing second, for many growers, it can be the more common kind of flushing they will ever do. It is this flushing, which can be very useful when plants have nutrient deficiencies, or they are showing signs of toxicity.

Growers may be doing everything right, and still they find their plants are exhibiting these symptoms. It can be frustrating, and as they try to correct these problems, they make matters worse and risk losing all their crops.

In most cases, it is the mineral buildup as seen above which causes these issues. There are different methods you can use depending on system type. As we saw, a DWC system or an aeroponics system doesn’t have any growing medium. Flushing this can be as easy as draining your tank and making a complete swap of solutions.

The reason being, there is no growing medium to hold these excess nutrients. If you are using coco coir, Rockwool or any other soilless growing media, then this can be more intensive. To do this, you will need a solution to be pulled through your medium to flush out the excess salts.

As we saw above, you can purchase dedicated flushing mixes, although, you can do this with a diluted solution. A diluted solution may be advisable, as your crops will already be accustomed to this, albeit in a stronger ratio.

Fertilizers can be weakened to 1/8th strength, adding to this, you will need between five and ten times the regular amount you feed to your plants.

Many growers may skip this step, carry out a full system flush, and start again. While this is the definitive way of knowing what your nutrient levels are, and what your pH level is, this can be a solution to correct your nutrient lockout or deficiencies without putting a halt to your system and cleaning while it is full of plants.

Do I need to flush with Organic Fertilizers?

Organic fertilizers work in different ways when they are in a hydroponic system. Many growers do make their own rather than option to purchase the regular three-pack-solution of nutrients.

If you use organic fertilizers, it will be a case of monitoring systems to check the TDS, the PPM and the pH level. In many cases you can find out there is no need to flush during transition as the type of nutrients being administered isn’t changing to such an extent.

Generally speaking, organic will have microorganisms which are breaking down before being fed to plants. This does however take place in soils or growing mediums. Some growers will still flush their system with fresh water in the final week to be sure there is no ill effect.

One thing to notice is there will be no salt build up when using organic nutrients as there isn’t the same composition of salts that normally causes issues.

Flushing Systems for Cleansing Purposes

If you are flushing to keep your system clean, you will find the steps are the same regardless of nutrients used. The only difference being the kind of system you have. Here are the basic steps of flushing to keep your system clean:

Draining your reservoir

If using a water pump, drain down suing this and a run-off hose. Water levels should reach the top of your pump where you then scoop out the remaining couple of inches. Some reservoirs come with drain valves, if you have a drain area, you can drain directly by using this.

Cleaning the Reservoir

Remove any sediment or algae and then top up with water and use the hydrogen peroxide cleaning method for sterilization. This will be easier to clean than using bleach as this needs triple flushing to remove all traces.

Fill the Tank

When cleaned, rinsed and wiped dry, you can fill your system and let it run before checking the pH levels. You can then add your new batch of nutrients and re-check your readings. When these are in line, you can begin adding your plants to your system.


As you can see, there are a couple of reasons why and how you can flush your systems. Not every method works for every grower because no two crops are the same. Many growers experiment to find the optimal flushing methods.

This is more the case during transition as there is more of a final effect on the resulting crops (crop dependent); however, this kind of flushing can leave crops tasting more natural.

This alone makes flushing during the final week of growth worthwhile. Having a bumper crop that doesn’t contain any taste of nutrients will be hard to beat in anyone’s book. Not to mention, it can make cleaning your system easier once that time comes around.

Is it Possible to Overwater Hydroponics?

Many growers understand that their plants will be growing in a sterile system that is based on water, and without soil. Therefore, when they are asked the questi0on whether or not it is possible to overwater plants in these kind of systems, it can cause some serious thought.

Is it possible to overwater hydroponics? Yes, it is possible to overwater hydroponic plants. There many different facets and reasons why this can happen. Much of it down to the type of system. However, this is what we will look at here.

We will see the areas of weakness in each system, and highlight what new growers need to do to be sure they don’t overwater their plants and cause problems.

What are they types of hydroponic systems?

There are six basic types of hydroponic systems, and the process for delivering water, oxygen, nutrients, and light can be very different between each of these.

  1. Deepwater Culture (DWC) – A DWC system is simple in construction. The system comprises of a reservoir and a lid or raft, which has holes cut into it for the plants to be suspended. The tips of the roots will hang into the nutrient solution while there is an air pocket where the upper roots can absorb oxygen.
  2. Nutrient Film Technique (NFT) This system comprises shallow tubes or troughs where water is pumped through a water pump up to the highest point. From here, the troughs angle downward, and by the force of gravity the solution runs back down and makes its way into the reservoir. The tips of the roots are bathed in this thin stream of solution as it runs under the net pot and the root tips.
  3.  Aeroponics – This method doesn’t use any growing medium like other hydroponic systems. Rather, plants are suspended above water jets, which spray or mist the roots with nutrients and water.
  4. Wicking SystemsPlants are rooted in a growing medium, which can absorb water. This upper container sits above a reservoir where a wick passes through the bottom of the container into the solution. Water makes its way up the wick and will soak into the growing medium where the plants can make best use of the nutrients.
  5. Ebb & FlowThese are also known as flood and drain systems. In operation, a flood bed will be filled with a water and nutrient solution, which soaks into the growing medium. Once the pump cuts off by use of a timer, the solution drains back into the reservoir.
  6. Drip Systems – With these systems, water is pumped through small tubing where it drips onto the growing medium and the plant roots. From there, it drains to the bottom of the pot and makes its way back into the reservoir.

Overwatering in hydroponics can take a couple of different forms depending how you look at it. If you take each system, it is easy to point at areas where it appears a grower is over watering. Here is a quick look at how they could be overwatered.

  • DWC the reservoir can be filled to high with nutrient solution. This leaves the growing medium saturated all the way through rather than moist at the bottom. One other thing is why plants don’t drown, and that is thanks to an air pump and air stones where the water is filled with dissolved oxygen.
  • NFT Systems can suffer from the same problems as DWC. If they have cups, which sit to a certain level, and the nutrient solution is pumping to fast so the height reaches the growing medium, then this will be saturated as well as the roots being submerged.
  • Flood and Drain systems can easily overwater plants if the incorrect growing medium is used and it retains too much moisture. Add to this the frequency of flooding the bed. Do this too frequent and plants won’t be able to absorb enough oxygen. Any media needs to drain sufficiently while remaining moist enough between soakings.
  • Drips systems can be one of the easiest to control water, yet if your pots don’t have sufficient drainage or the drain hole blocks, these can fill full of water and subsequently overwater your plants.

Growing Media for Hydroponics

One of the primary reasons plants are over watered is because the incorrect growing medium is used in a system, or it is directly exposed to the solution and remains too wet. The easiest way to prevent this is to understand how each of these mediums perform in retaining moisture, and how they can let oxygen find its way to the roots.

Hydroton Pebbles

These expanded clay pellets are manufactured under high heat. The resulting balls are porous and will retain moisture while offering plenty of support for larger plants. These soak up moisture, yet they don’t remain saturated once the source of the water leaves the growing area. The large gaps between the balls allow water to drain off quickly. You can find these in flood and drain and drip systems more than other systems.


This is one of the more common growing mediums in use, yet Rockwool has the downside of soaking up lots of water. It is this, which when touching a water source can leave plants sitting in water, and leads to rapid suffocation. This will drain, yet it remains moist for longer periods. These can be found in starter plugs or larger blocks. In use, they are often used to cut back on the use of electricity to feed solution to the plants.


You can find this in either fiber or chips, and each type offers different water retention properties. Both were once considered a waste product of the coconut industry, yet they were found to be one of the best materials for hydroponic gardens. The coco chips allow more oxygen between, so they have a greater degree of drainage. The fiber will hold more moisture and drain slower.

Perlite and Vermiculite

These are two different compounds yet function in a very similar way. They can both wick moisture easily, and are often used as a mixture with another growing media. If these are watered too frequently, they can retain too much water and suffocate plants. Also because of their small size, the amount of oxygen, which can penetrate, is reduced.

River Rock

You can find this in any good garden center or home improvement stores. While they don’t offer any capacity for soaking up moisture, they can be used to create good drainage. You often find these used in containers where they are mixed with coco chips. This can retain moisture and will allow lots of oxygen to plants. Many growers use these in the bottom of pots or containers so the growing media doesn’t sit in a puddle of water and remain saturated. If using smaller rocks, it is possible to use these by themselves such as in drip systems, yet watering schedules will have to be adjusted to prevent root drying out.

Oxygen is Key to Prevent Over-Watering

Many growers understand that plants absorb carbon dioxide and throw out oxygen when they photosynthesize. This they do in the right environment during the day, however, they also need to respire. This is where they absorb oxygen through their rooting systems.

Once roots end up standing in water, they suffocate. This means they are unable to breath, and as the roots are unable to do anything, they can quickly begin to rot.

It is this reason why the choice of growing medium is vital for each kind of system. Growers will need to find the best for their needs as well as make sure that any water levels or frequency of watering are adjusted accordingly. Knowing what to do here can vary between gardens, and a grower will need to carry out careful research to find the best settings.

There are things growers can do to help, and that is by the introduction of extra oxygen. Flood and drain systems and deep-water culture will allow plants pockets of oxygen, yet these are administered in different ways. However, they can still benefit by the introduction of air stones or air diffusers. These use an air pump to fill the water with tiny bubbles, and thus deliver this to the roots.

There are two things that can reduce the impact of this that grower’s need to be aware of. First is the buildup of algae. Live Science defines Algaeas a “diverse group of aquatic organisms that have the ability to conduct photosynthesis.”

These will absorb oxygen from the water for their own growth. Growers can help rid systems from this by the addition of some hydrogen peroxide. This is also a great way to kill other bacteria.

Next is the temperature of the solution. It causes other problems if it is too high, yet a temperature that is too high will reduce the solutions capability of retaining the dissolved oxygen.


Growers may not intentionally over water their plants, and they may be doing most things right, yet as soon as the amount of oxygen in the water reduces, be it from a lack of air pump, or the growing medium isn’t suitable for their indoor garden, then plants will suffer.

These are the two primary reasons plants are over watered, and with some careful thought and experimentation, every grower can eradicate these issues to make sure overwatering is no longer an issue.

This is Why Hydroponic Tomatoes Split

One of the best crops any hydroponic grower can grow is fresh tomatoes. These can make a huge dent in any grocery bill, and they are in most cases larger and tastier than store bought varieties. Not only this, but they can be grown throughout the year instead of just being enjoyed throughout the summer months.

One of the most frustrating things for any hydroponic tomatoes grower is to see their fruits ripening nicely, and the next thing they see is they have split.

Here, we will look at the reasons why hydroponic tomatoes split. Gardeners shouldn’t be frustrated and think this is a problem with hydroponics because the exact thing can happen with solid grown varieties as well.

Before looking at why they split, here is a quick summary of what affects their overall growth, and possible factors that lead to split tomatoes skins.

  • Nutrients: Tomatoes require specific nutrients in comparison to other crops. They can be heavy feeders, so they require nutrients they can easily absorb, and have an equal balance, which are nitrogen rich.
  • Temperatures: Tomatoes need a temperature of between 55-85 degrees Fahrenheit; they can however handle higher temperatures up to no higher than around 90 degrees Fahrenheit.
  • Light: This can be one of the most vital things for good tomato growth. They will need around five or six hours of good strong light, be it sun or artificial lighting.
  • Environmental conditions: Tomatoes suffer if they are in windy conditions, vast temperature swings or there are cases of insects or other plant disease. Many of these can be negated in indoor gardening, yet the possibilities are still present.
  • Pollination: For growth, fruiting tomatoes do need pollination. If a grower won’t be manually pollinating, they do need to use wind or the presence of insects to do this.

Types of Tomato Splits

Growers can be faced with two different types of splits or cracks on their tomatoes. These you can see here:

  • Radial cracking. This type of split will run down the length of the tomato from its stem to the bottom blossoming end of the fruit.
  • Concentric cracking.  Circular cracking at the top of the tomato and make their way around the stem. These splits don’t appear too appetizing yet they are not as serious as the previous splits.

Growers will find that if their first few tomatoes show splits, and then there is a high likelihood that all their fruits will start splitting in the same manner.

Why do tomatoes split?

Tomatoes most often split when they begin to ripen; however, the main reason is they have a huge intake of water. Once they do this, the skins are not elastic enough to allow for these excess fluids and will resist as much as they can before giving way and finally splitting or cracking.

Another reason they can split is a sudden temperature change, the way this causes fruits to split is the increase of gasses inside the fruits. This then has the same issue as too many absorbed fluids, there is no skin elasticity and splits or cracks form.

One final area where tomatoes are prone to splits is a sudden drop in the EC levels of nutrients. This is more common with outdoor gardens, and occurs if it rains heavily for prolonged periods just as the fruits are ripening. This sounds similar to the plants taking on more water, yet it is because the nutrient levels are lower.

You may be thinking how you can stop tomatoes absorbing too much water in a hydroponic system. The actual system itself will affect how tomatoes grow because these kinds of plants are not suitable for every kind of system.

Here we will take a look at all you need to know about everything which relates to growing healthy tomatoes without high chances of splitting or cracking.

First, we will look at the best kinds of tomatoes to grow in hydroponics as this also has a bearing on splits and cracks.

Best Hydroponic Tomato Varieties

One of the errors that new growers can make is by not understanding the best types of tomatoes to grow. While there are countless varieties, all of these fall under two kinds.

  • Determinate: These are bush kinds of tomatoes which rather than growing upward, they spread across the ground. This kind is better for hydroponic growers because they will grow to certain heights, which can be around two to four feet. Once these flower and bear fruits, the growth of the plant will be reduced
  • Indeterminate: This kind are what we usually see and are vining plants that like to grow upward. These don’t have any upward limit for their growth, and with the right pruning, there is no limit to the length they can grow, or how much fruit they can bear.

Lighting for Hydroponic Tomatoes

Because tomatoes are often grown outside, they will stop bearing fruits, as the winters get ever closer. Fruit size on tomatoes plants is a direct reflection on the amount of light they receive. This in turn decides the degree of photosynthesis that can occur for each plant, and thus affect size and quality of fruits.

For good growth, tomatoes like between eight and ten hours per day of light. Nevertheless, some varieties produce high yields when they have up to eighteen hours per day of good light.

Once your plants mature, they need eight hours of darkness so they can fully respire, and following this, you can give plants sixteen hours per day for maximum fruit production.

When it comes to lighting choices, Metal Halides are proven to deliver the best growth because of the powerful light output. Fluorescent tubes and LED’s can be used, yet the grow isn’t as much.

Best Temperatures for Hydroponic Tomatoes

Tomatoes are warm weather crops, so they like temperatures between 65 and 77 degrees Fahrenheit in the day. They are quite hard and can stand a temperature that falls no lower than 55, or reaches up to 90 degrees Fahrenheit.

Temperatures that fall or rise outside this range can kill tomatoes, so as a grower, you will need to maintain consistent temperatures in this range. One way to be sure you keep these temperatures is by using a grow tent. These enclosed spaces make it easier to warm, easier to control and more cost effective to do so.

Nutrients, EC and pH Levels for Hydroponic Systems

Tomatoes are fussy for their requirements, and it is this reason why they are often skipped for new growers. To obtain the best, they do need a few different elements that are in the correct ratios.

Growers can use 3-pack nutrient mixes, yet if they wish to maximize the yields, there are also some specific mixes solely for use with tomatoes, or 2-part mixes which are more geared to these plants.

Tomatoes require high levels of potassium, nitrogen and phosphorous, and for the pH they like the range of 5.8 to 6.3 which is a little higher than for other plants. Nutrients will need to be mixed correctly because the EC levels for optimum growth need to be between 2.0 and 3.5 milliMhos.

Tomatoes will show you quickly if they are deficient in anything. By any of the following:

  • Yellowing leaves signal low nutrients or high pH
  • Curling leaves or red stems are a low pH
  • Leaves which curl down are signs of high nutrient levels
  • Flowers which begin falling early show a potassium deficiency

Growing Media and Hydroponic Systems

This one area can lead to too much water in your plants. Not only this, but the growing medium will need to deliver support for these plants as they will be heavy once they begin bearing fruits.

  • Hydroton clay pellets – used in DWC, NFT and drip systems
  • Coco coir – use in passive systems
  • Rockwool – ideal for ebb and flow, and drip systems
  • Vermiculite and Perlite – Used in drip systems. NFT or can be mixed with any other medium

All systems can be suitable for tomatoes, yet as they feed heavy, and the growers need to be sure they can control the amount of water at harvest time, the best two systems can be the drip system and the flood and drain system.

Both of these are ideal as a grower can have more control over the amount of water tomatoes can receive.


It can be almost impossible to prevent tomatoes splitting; yet being on top of everything can reduce the effects. Once they start, it can mean they are prone to rotting and parasites can get inside.

If they split, the good news is they are still edible, although they may not look as appealing. Growers can look forward to healthy fruits, and as soon as they see a sign of any split, it could be a sign to begin harvesting early as this can be one way to be sure they won’t grow any bigger and suffer from this issue.

Can You Use Tap Water for Hydroponics?

Many individuals understand that hydroponics is the growing of plants without soil. Rather, the root systems are either supported in a growing medium, or suspended with the tips of their roots dangling in the nutrient rich water.

One of the most common mistakes new growers make before they fully research hydroponics is the use of tap water. Therefore, this begs the question of whether or not; you can use the water from a faucet in a hydroponic system?

The answer to this question is yes, water from the faucet can be used, but not as it is. Growers need to carry out additional steps to protect your plants from the chemicals and minerals, which are present, and will negatively affect the health of plants.

Here we will look at the reasons why water from a faucet isn’t ideal, what can be done for its preparation so it can be used, and what are the other water options open to growers.

What is in Tap Water?

In most areas, it can be safe to drink water from the faucet; surely, this means it is good enough for plants? However, this may not be the case. In soil gardens, it may be because they are taking the nutrients they need from the soil. In a hydroponic system, the nutrients will be provided in the solution from the grower.

It is because of this that growers need to understand what is in regular faucet water, and why it makes such a difference.

Tap water is treated to remove bacteria and all the impurities. This makes it safe for our use, yet it is these treatments, which render it no use to a hydroponic plant.

Here is the process they generally use to clean and purify water before it is available for home use.

  1. Chlorine and or Chloramines are added to kill off harmful waterborne bacteria
  2. Aluminum sulfate is added which makes impurities coagulate (stick together)
  3. Impurities settle where the clear water is then removed and filtered by various means
  4. The water has its pH levels adjusted that are safe for human use

Chloramines and Chlorine

Chlorine is the most common addition to water to kill off waterborne bacteria. However, this is also one of the micronutrients that is needed by plants, yet in minute quantities. As a result, this would mean a grower would not have to add any; the problem is, in concentrated nutrient mixes, these chloramines and chlorine are already present.

This addition means plants will absorb too much. Results of this mistake can be stunted growth, and the beneficial bacteria on roots will be killed off.

Hard Water and Soft Water

These two terms are often heard and can have a major impact on hydroponics. Hard water is where you can see the accumulation of hard crystalline substances on the ends of faucets and showerheads. It is also the hard water, which leads to the breakdown of dishwashers and washing machines.

When you live in a hard water area, this contains more minerals, and it is these which bind together to form these deposits. When you look at how it affects hydroponic plants, there will be a much higher level of minerals in the water, some of which they only need small amounts.

Two primary culprits are magnesium and calcium. While these are necessary for plants to thrive, they are only required in small amounts. With the increase of these two minerals, the PPM (Parts per Million) can increase dramatically. For the majority of water from the faucet, the PPM will be 150 part per million as a minimum of salts that are unwanted.

This causes problems with nutrient absorption in plants. Most of the nutrient mixes you can purchase are all designed to be mixed in pH neutral water. When the faucet water has an increased pH, this can cause nutrient lockout. Issues you can see are wilting plants or worse.

If growers attempt to adjust the pH levels for hard and soft water, they can complicate matters for themselves. The pH adjusters will contain potassium and phosphorous which are common nutrients in the mixtures.

To deal with hard water problems, there is usually only one course of action. That is the use of a Reverse Osmosis system or other filtration system to remove impurities and bring water back to a neutral pH level.

Hydroponics and the Use of Chelates

When companies make the nutrient solutions, they need something to make sure these are suspended in the solution. This is the purpose of chelates. If it weren’t for these, there would be some of the system elements that begin to latch onto each other. Once this happens, they become useless to the plants.

Chelates are formed in several ways and can be chemicals such as ETDA or an organic compound like humic acid. One of the key problems here is that as Chlorine is a micronutrient and will be affected by the chelates. Once it meets them, there is more likely an uptake of this from your tap water into your plants.

Preparing Water for Hydroponics Use

There are a few ways you can prepare water from the faucet for use in a hydroponic system. This does depend on what you are looking to clear from the water, and each element could take another step of preparation.

Removing chlorine from water can be quite simple yet it is a lengthy time consuming process. The first step for any of the processes is to find out what your local municipal water supplier does to their water in way of adding chlorine or chloramines.

Here are the ways to begin preparing water from the faucet for use in your hydroponic system.

Removing Chlorine

Although this takes time, it can be one of the easiest things to remove from tap water. All you need to do is let your water sit in strong direct sunlight for a period of 24-hours. Here the UV rays break this down and the chlorine can escape from the water. This off gassing is easy yet if you have large amounts of water to deal with, then it could be difficult to accomplish.

Removing Chloramine

This compound doesn’t break down in the same fashion. However, it can be easy to treat water if it has been treated with chloramine. You can buy Campden Tablets, which you add, one tablet per every 20 gallons of water. The good things with these ae they can also remove both chloramines and chlorine. Other ways are to run your water through an activated carbon filter. These are similar to water filters you purchase to cleanse drinking water.

Hard Water and PPM

This treatment can be one of the hardest as it takes repeated testing. The aim is to remove the calcium and magnesium. A basic water filter can suffice for small systems, yet you will need to change these quite often. The nest way if by using reverse osmosis filters. These can be fitted to home plumbing systems, so you can gain benefits in other areas.

If you buy one that is specific for hydroponics use, these come with carbon and sediment filters in place. While these can be costly, they work out cheaper than losing crops because of using tap water in your system. Another downside is they can produce wastewater while they are producing the clean water.

Additional Water Solutions

Here are a few other ways you can get safe water for use in your hydroponic system.

Harvesting Rainwater

This can be one of the most cost effective ways of collecting water for your indoor garden, but a water collection system will needs some construction to be sure it leaves you with the cleanest possible water. Building a system can be as easy as placing large drums at the bottom of downspouts. Nevertheless, you will still need to make sure excess water can escape down the drains as you can cause flooding around the home if you bypass your drain system.

One thing to note is there are some local laws, which dictate how you can go about collecting rainwater. Before commencing for any rainwater collection system, check local and federal regulations.

Distilled water

This can be purchased almost anywhere, and is seen as a great option for its ability to provide a sterile environment for hydroponics. None of the previously mentioned contaminants is found in distilled water, yet you may need to be wary of the lack of calcium and magnesium, as all traces of this will be removed. If your nutrients don’t contain enough of these two minerals, you can purchase a dedicated calcium and magnesium solution to help adjust these levels. Care should be taken as you can be just be creating hard water again.

Deionized Water

This is created by taking regular water and exposing it to electrically charged and processed to remove all of the excess salts from the water. It is very pure and after treatment leaves you with a solution which is very similar to distilled water.  


New growers need to understand that water from the faucet is very different from other forms. In some areas, it may be suitable for use, yet a few miles down the road can be a very different story. Water is the lifeblood of any hydroponic system, and if this isn’t right to begin with, then there will be no going forward to have a successful garden.

How to Transfer Plants from Hydroponics to Soil

Many growers who have hydroponic gardens are happy with the plants and crops they grow, and that is sufficient for their needs. There are however others who use hydroponics as a means of growing plants and then transferring them to soil.

This can be for several reasons, yet no matter what the reason for doing so, there are some steps and things growers need to do to ensure their plants make the transition without receiving a shock to their system and suffering as a result.

The same can be done in reverse where plants are moved from soil to a hydroponic system, however, for a method it can be easier to accomplish, as there is no soil to contend with on your plants.

Why Would I Transplant into Soil?

One of the primary reasons for doing this is to use hydroponics as a means of having a healthy start to an outdoor garden. When outdoor growing seasons begin, there is the choice of growing from seeds, or from seedlings.

Seeds take time and there can be some failure rates encountered, commercially bought seedlings can be expensive and on certain occasions, they can be hard to find.

Any grower, who has an outdoor garden, can take advantage of growing their own seedlings in a fraction of the time so they can make the most of their outdoor garden and the growing season with fewer failures.

These indoor systems can also help alleviate any issues that crop up with the unexpected forces of nature, which can interrupt what should be a successful start to a growing season. Not only that, but using hydroponics to start off your seedlings means you are ready to go as soon as you harvest outside after some slight soil preparation.

It doesn’t matter if you are transplanting out of choice, or because it is essential you do so, there are some things to be wary of. From what can easily be a daunting task can become straightforward for any different hydroponic scenario that you face.

Transplanting Hydroponic Clones and Cuttings

While seeds are an option for gardeners, there is more of a swing toward using cuttings and seedlings, hence the increase in the need for transplanting from a hydroponic system back into soil.

The two most common areas of hydroponics that take place before these transplants are the domed incubation grow trays where small rockwool starter plugs are used, or the more complicated mist propagation systems.

The great news for gardeners is that both of these systems are perfect for outdoor gardeners to use, and are compatible with their soil systems once the seedlings or cuttings have begun to show a good healthy rooting structure.

One primary reason this is a good option apart from getting a kick-start, and missing the chances of bad weather is that growers can over time find an ideal mix of environmental factors, genetics and mix of nutrients. For this reason, many experienced growers preserve the donor plants. Here they can carry on the genetics of the plants and thus they are ensured a level of consistency for good harvests.

One other factor that growers have no need to grow from seeds which could deliver either male or female plants. This is another level of consistency as they will be aware of what they have when they begin growing their seedlings or cuttings.

Steps for Transplanting into Soil

Here are the easy to follow steps for transplanting into soil from your hydroponic system.

  • Take a suitably sized pot, the larger the plant, the bigger the pot you will require. These should be roughly four to six inches wide. Plants being transplanted into soil will need more space for their roots. Give them around four to six inches of space to allow them to grow.
  • Fill it with a growing medium that adds some buffer for your plants until they are ready to be fully transplanted into gardens. Many growers opt for soilless peat mixtures, which have a better pH than planting directly into soil.
  • Make a hole in the center of the pot, which is larger than the plants rooting system, and the starter plug if used. If you have plants, which are growing together, you will need to separate the roots carefully as this can cause plant shock easily.
  • Sprinkle the hole with mycorrhiza. This beneficial fungus helps as a growth enhancer. This helps plants absorb nutrients from soil as it helps to increase the area of absorption.
  • Place the plant in the hole and then cover with additional dirt
  • Once you have planted, you do need to water immediately. Hydroponic plants are accustomed to being watered regularly to help minimize plant shock levels they will experience. You can use a quarter strength nutrient solution in the beginning until they start finding their own nutrients from the earth.
  • After about a week, you can cut back on watering until you only have to water as the top inch of soil is dry.

One you have done this your plants will need to be in areas with plenty of light, yet they may not be directly accustomed to the outside temperatures. There will be a period of hardening off they need to go through for a week before they can last in outdoor temperatures.

Soil Transplanting Tips

If your plant is large, it can help to trim back some of the foliage. This pruning will help the plants, as they don’t need to search for nutrients for more leaves and can start to grow steadily.

Most gardeners who use rockwool cubes or plugs intend to transplant into soil. A gardener that uses the larger cubes around the six-inch size won’t be looking to move plants into an outdoor garden or soil filled pots.

Net pots will be entwined with a plants rooting system if plants are more than a few weeks old. If these do need to be planted in soil, it can be a case of planting the entire net pot as well as the plant. Trying to remove the intricate rooting system can kill the plant.

Plant Shock When Moving into Soil

If you have done everything right, your plants will take hold and begin growing as they should. However, if they are suffering from shock, there are some signs you will notice. This can happen quickly, or it can happen over the first couple of weeks after moving into soil.

Leaves can turn yellow to brown and may wither up and darken. These can fall from the plant with a light touch. At this stage, leaves and stems begin to wilt and dry.

There are some things you can do to try and cure plant shock, yet these may not work in every case.

  • Trimming back the plant by at least one-third can help plants focus on their roots.
  • Keep rooting systems moist is vital. Because there is a difference in the watering, there will be more onus on good drainage through the soil. It can be easy for plants to find themselves in standing water.
  • Add a water and sugar solution. While this isn’t 100% proven, it can help and even if it doesn’t work, it won’t harm your plants.


Moving plants from a hydroponic system is a feasible option for many gardeners. By taking this route, even if it can be a little hard for new growers can be worth the effort. Growers can have seedlings or growing cuttings that offers up more plants to move outside.

Rather than using seeds and having to wait, plants will be instantly growing. This offers the chance to plant more crops throughout the year they may have previously not been able to.

If things don’t work out as intended, there is still the option for growers to carry on growing in their system. It can be a win-win situation, and there will be less overall wasted effort in the outdoor side of a garden.

How Does Hydroponics Not Drown The Plants?

Hydroponics systems are based around plants being grown in water, so why don’t plants drown? This is one of the first things, which confuses possible hydroponic growers, and it can be enough to prevent them from starting their own garden.

While there is quite a lot to understand about hydroponics, one of the very first things any growers comes to learn is the reason why their plants won’t drown in a functioning system. There is of course some reasons why plants will suffocate and drown, yet these are in many cases not the fault of the grower and are the fault of an outside influence.

Here we will look at why plants generally don’t drown, and how they grow in each kind of system.

Why Plants Don’t Drown in Hydroponics – The Simple Answer

Hydroponics systems do not drown plants because the water is constantly oxygenated, circulated, filtered, and refreshed. The system is designed to keep plants from becoming oxygen-deprived.

At this point, it is worth making a comparison against soil and hydroponic systems. Drowning plants isn’t something new, as you will see.

Any plant in soil can be over watered. Growers may be worried their plants are not receiving enough water, and this is more the case if they see dry soil around their crops. After irrigating them with the hose, they can be leading their plants to a premature death if they are not careful.

In soil, this over-watering stops any oxygen from penetrating the soil and getting to the roots of the plants. It may seem obvious that they absorb oxygen through their leaves, but this just isn’t the case. The pockets of air underground will be gone, and this leaves the plants no way to carry out the respiration they need for survival. In a best case, they will still be suffering from stunted growth, wilted leaves or both.

After a short period, fungi begins growing on the roots as the water and nutrient uptake slows. Now the roots are covered in water, they are in the perfect conditions for this fungus to take hold. The more common strains are Pythium, Rhizoctonia and Phytophthora, and all of these will grow on roots, which are under water.

From this, there is the one thing gardeners of all types hate to face, and that is root rot. If you check the roots in your hydroponic system, they should be white. Colors can change from brown, to gray and black depending on the degree of rot.

In hydroponic systems, the way they are designed, roots are never wholly submerged for extended periods. The ebb and flow system can be the one system where all the root system is submerged, yet this is on a timed schedule and can be for a limited period a few times per day. Aside from that, the roots are exposed.

This isn’t to say plants can’t drown and suffer from root rot. Many variables in hydroponics lead to this. Now, we will look at more reasons why plants don’t drown in a correctly functioning system.

How Hydroponic Systems Oxygenate Water

There are a variety of methods hydroponic systems use to keep the water oxygenated, allowing the plants to breathe efficiently. This does depend on the system because some rely on electrical pumps to do this while some simple systems don’t oxygenate the water as such, yet they make sure oxygen is available to the plants.

Depending on the way the system is set up, some of these methods include:

  • Air Stones – Many gardeners use air stones regardless of the type of system they are running. You can’t have too much dissolved oxygen in your system. These stones fit in the end of plastic tubes, and these fit onto a pump that sits outside the reservoir. This will suck air in and create thousands of tiny bubbles. Smaller bubbles are better as they dissolve into the water easier.
  • Diffuser Tubes and Rings – These work in much the same way as air stones but cover a larger area. They are made of bendable tubes that are filled with evenly spaced holes. These produce streams of small bubbles just like air stones.
  • Automatic Water Recycling – This method is seen in Ebb & Flow setups. At regular intervals, water is pumped into the flood table by means of a water pump. Once the pumping period is over, the water drains back into the reservoir. This action can create oxygen, yet many growers still use the above to be sure there is dissolved oxygen in the water. The main source of oxygen will be as the water drains and leaves the roots exposed between flood cycles.
  • Hanging Roots – What many people don’t realize is that not every inch of the plant roots are submerged. In some systems such as Kratky or DWC, it is only the tips of the roots that are continually touching the water. The remaining portion is exposed so there is an uptake of oxygen. Aeroponics systems go one-step further and leave the roots suspended in mid-air. These are misted at intervals. This delivers water and nutrients while the rest of the time roots hang and soak up oxygen.

Different Kinds of Hydroponics Systems

Here we will look at each system, how they work and why plants don’t drown in them under normal conditions.

Wick Systems

A wick system works by capillary action. You will have two containers, one that sits on the top of the first. The bottom being the reservoir, and the top containing the growing medium and plants.  The growing medium needs to one that will absorb moisture from the wick. Coco coir or perlite being two of the more common. Plants need to sit close to the water, as there are limits to how far water can move before gravity stops it. Plant roots will have constant access to oxygen, as the growing medium never becomes overly saturated.

Water Culture Systems

These are one of the simplest systems to build and use, and the simplest being the Kratky method, yet this doesn’t use any pumps. The plants remain suspended above the reservoir in grow pots or in foam collars. Under the lid of the reservoir will be an air space where the roots hang before their tips submerge into the nutrients. The rest of the upper roots are free to absorb oxygen.  These systems make use of air pumps, yet the water doesn’t circulate via a water pump.

Drip Systems

These can take on many forms when growers build their systems, yet the principle is the same. Plants will be in a growing medium such as Hydroton pebbles. Small tubes from drip emitters will feed small amounts of water around the roots. This keeps the growing medium moist but because the water drains so well, this passes straight through and makes its way back to the reservoir. 

These are suitable for larger plants and one of the most popular being the Dutch Bucket System, which is very easy to build.

Ebb & Flow Systems

These systems take a periodic approach by use of an electrical timer. It is this, which will deliver nutrients and water to the flood table. In this is a drain valve that stops the water running too high and submerging all the plants. This drains the solution back to the tank until the pump stops.

Once this happens, the flood and drain system automatically drains back to the reservoir where it will wait until the next cycle. Roots can take up oxygen in between these cycles. These can be one of the easiest systems to maintain.

Nutrient Film System

Nutrient Film Systems use closed channels like downspouts. These have holes in the top where net cups sit which hold the plants. A thin stream of solution continually runs down these while the tip of the roots are bathed in the solution. The upper most part of the roots are exposed to oxygen. These are made on a slope so that once the pump pushes water to the highest point; gravity pulls it back to the reservoir.

These NFT systems are easy to build and great for smaller plants and are one of the most popular because of the fast turns these kinds of plants deliver.

Aeroponics Systems

In an Aeroponic System, the plants are suspended with the roots remaining free and open to oxygen. The roots are only misted with a fine nutrient solution intermittently to provide the resources needed for growth. The inside of an aeroponics system is typically humid and delivers some of the best conditions for maximum growth. While aeroponic systems make sense, they can be challenging to build and maintain. There is also an array of factors growers need to calculate like the rate of misting, water droplet size.


Most of the hydroponic systems mentioned are designed so they can prevent plants from drowning. The exceptions being the DWC and the Kratky systems. These are the only two where water levels can be too high and too much of the rooting system can be submerged.

The main problems growers face is plant suffocation, and one of the fastest ways for this to happen is the air pump breaks or there is a power outage for long periods. If this happens, it can render a hydroponic system useless and it won’t take long for plants to suffer.

With regard to drowning, the major thing a grower needs to calculate is how fast and how frequent to pump the solution to their plants. These things aside, most of these systems will run happily, and the plants can make most use of the nutreint rich solution.