Can You Use Seasol For Hydroponics?

Hydroponics gardeners are always on the lookout for the best additives or nutrients to use in their system that offer the best results.

One of the prominent names that come up is that of Seasol. It may lead to some confusion for new gardeners as Seasol is a brand name, and rather than being a fertilizer, the products are a tonic.

Since a tonic is not something you typically associate with delivering nutrients to your plants in the same sense as other two- or three-part nutrient packs. Many gardeners often ask the same question.

Can you use Seasol for hydroponics? Seasol can be used in your hydroponics system without any adverse effects. It is an effective growth stimulant and plant tonic made from seaweed in Australia. Seasol offers more than just promoting healthy, vigorous growth in plants; it also helps increase resistance to attacks from fungi and insects. Besides this, it helps reduce symptoms of stress from excessive heat.

What Is Seasol?

Seasol is an Australian company that offers a wide range of treatments for around the garden and yard. A number of these deal with lawns and grass, while others are suited to flowers and fruits. While some are granular or pellets, there are a few that are liquid and thus soluble.

Seasol original and Seasol Gold are the two main products you could use in your hydroponics system. Before proceeding, these won’t replace your nutrients, they are an addition, and the doses would be very weak based on the volume of water in your system.

  • Hydroponic seedlings would use 2 mL per gallon of water.
  • Established hydroponic would use 4 mL per gallon of water in your system.

Here you can find the benefits and significant features of adding Seasol and Seasol Gold into your hydroponic system. Note some are specific to the soil as it is intended as an additive to soil-grown crops.

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  • Vigorous root growth and healthy soil microorganisms are stimulated.
  • Encourages vigorous flowering and fruiting, as well as overall garden health.
  • It helps plants deal with external stressors, including heat, drought, and frost.
  • Improves the resilience of plants against insects and fungal attacks.
  • Use any time your plants need a boost.
  • Reduces transplant shock and improves seed germination.
  • As a result of the increased nutrient uptake, fertilizers and nutrients are more effective when used.

Seasol Gold

Seasol Gold does all the same as the regular solution and builds on it.

  • Unique proprietary formulation to enhance seaweed efficiency and advantage to plants.
  • It is fortified with calcium and other nutrients to give crops a boost during the growing season.
  • Promotes better nutrient uptake for robust, strong root development.
  • Improves the development and production of flowers and fruits.
  • Improves plant resilience to heat, drought, frost, pests, and disease by strengthening and boosting plant health.
  • It can be added at any time.

Helps tomatoes at the flowering time by the following.

  • Increases the overall amount of nitrogen and calcium in the soil.
  • Increases organic matter totals in soil.
  • Increases the amount of organic carbon in soils.
  • Soil microbe populations increase.

Seaweed is a brown alga, which they have used in agriculture for generations, but scientists had limited knowledge of its unique qualities.

Seasol is a 100% Australian liquid seaweed extract manufactured from Durvillea Potatorum, a unique kelp species found in the clean waters of Southern Australia.

The Great Southern Ocean’s huge seas wash masses of bull kelp onto the beaches of King Island, and it is here they harvest it from the beaches without touching any still in the wilderness. It is in Tasmania you find the only production plant in the world.

Seasol is a dynamic growth stimulant and plant tonic; it isn’t a fertilizer, and it gives benefits that a regular fertilizer can’t.

Why Use Seaweed Additives and Tonics?

While you can use Seasol and other seaweed-based additives, it is good to understand why these are so beneficial to your plants above different formulations, or even the benefits they offer besides your regular nutrients.

Liquid seaweed or Seasol is one of the best additions you can use on your hydroponics plants, although it could be the last thing on your mind when looking for crop additives.

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Not only are liquid seaweed solutions organic, but they also originate from a sustainable source and are harvested without harming the environment. Most seaweed-based remedies come from kelp, which can grow to be over 150 feet long.

It’s full of trace minerals like magnesium, potassium, zinc, iron, and nitrogen. Nitrogen is essential because it creates nitrate, which is a vital component for photosynthesis in plants.

Here are some benefits of using liquid seaweed additives in your garden or hydroponic system.

  • A liquid seaweed solution aids budding.
  • If applied ten days before harvesting, it can help extend the shelf life of fruits and vegetables.
  • If cut flowers are sprayed a day or two before cutting, they will last longer.
  • It can be used as a rooting solution. Place cuttings in a solution of liquid seaweed and water until they develop roots.
  • When applied to pasture crops, the algae boost nutrient uptake, protein content, and overall crop quality.
  • Seaweed extract increases crop yields, increases inorganic ingredient uptake from the soil, enhances stress resistance, and minimizes fruit storage loss.
  • On fruit, flowers, vegetables, lawns, and other plants promote vigorous development and help repel pests and illnesses.
  • Organic farming benefits from seaweed solutions.
  • Every micronutrient is present in chelated forms.

Related Questions

Can I use regular fertilizer in hydroponics? Although possible to use regular fertilizer in hydroponics, it is not recommended as they lack many chemicals found in hydroponic nutrients.

How often do you change the water in hydroponics? Hydroponic water needs to change every two to three weeks on average. If you add Seasol, ensure you check your pH levels as you may need to change more often or adjust with pH Up or pH Down.

What kind of fertilizer should I use for hydroponics? Measure six teaspoons of a high-quality fertilizer into the water. This will be from your part A if you have a multi-part pack. It would contain a 20-20-20 mix of 20 percent nitrogen, 20 percent phosphorous, and 20 percent potassium. You can add Seasol at the same time to boost macronutrients and trace elements, or you can add your Seasol later.

How Long Do Hydroponic Nutrients Last? You will find your nutrients last around 7 to 10 days; thus, you can see the addition of Seasol later means you can bolster the effectiveness of weaker nutrients when they are most needed.


Using Seasol in your hydroponics system can deliver many benefits to your crops and your yields.

One of the best things is that it won’t have any adverse effects if you stick to the recommended levels as you administer your dose. All you would need to do is check your pH, as this could impact your growth, yet since the dosage levels are low, you may not notice any difference.

Seasol can be a fantastic base to make your organic hydronic nutrients or add to them to offer what your other compounds don’t. If you do this, you’ll find many formulas use seaweed as a key component, and with Seasol, you are already there.

Seasol is a terrific addition and the safest way to give you crops a boost in vitality than anything else you can find on the market.

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