Can You Grow Avocado in a Hydroponics System?

When people think of growing in hydroponic systems, they tend to think of more popular vegetables and fruits like lettuce, peppers, tomatoes, and strawberries. However, with some careful tweaking, it can be possible to grow an Avocado tree in a hydroponic system.

Can you grow avocado in a hydroponics system? Yes, you can grow avocados in your hydroponic system when you give them the right growing conditions to thrive. The major drawback is the size of the tree when it reaches maturity, but tackling this early on can give you bumper crops of Avocado.

If you are up for the challenge and you want to start growing avocado in your hydroponic system, carry on reading, and all will be explained how you can have a healthy tree that won’t take up too much space.

Growing Hydroponic Avocado – Where to Start

One of the first things that you should know when starting to grow an avocado tree is, that you should be looking at growing two, the reason being when your trees finally reach pollination. There are two types, type A which sheds its pollen in the afternoon and is receptive to being pollinated in the morning, and type B which sheds pollen in the morning and is responsive to being pollinated in the afternoon.

If you are growing from seeds, you should note your tree won’t give the fruit of the same variety because they don’t breed as true to seed. When you have two types of avocado trees, these will grow and breed true to their variety.

With this in mind and the fact you will be running your hydroponic system for four years upward before seeing any fruits, you need to mimic everything for your trees as if they were growing in their natural habitat.

You will need warm temperatures and plenty of light. This is one reason why they are ideal for growing in sunny parts of the house or on an enclosed patio to avoid cold winter chills. One thing that is a must is your grow lights; these will need to be either LED growing lights, metal halide lamps, or high-pressure sodium light fixtures. We’ve written a complete guide to grow lights here to help you understand what to look out for and get your head around the terminology.

In the beginning pot size isn’t an essential factor, but it is discussed later as they do play a crucial part in the growth of your tree. The main thing is if you wish to grow from seeds or purchase trees that are already on their way. If you aren’t sure about what pot size to use, try our pot size guide. Trees taken from grafts are much better for growing fruit than ones that are grown from seeds. Varieties of avocado can be purchased directly from specialty retailers that deal with colder climates.

Steps of Growing an Avocado from Seed

If you decide to grow from seeds, you can find these online from tropical seed retailers or at a local nursery. Growing from seeds does take much longer, but there could be a higher sense of satisfaction when your tree starts sprouting up. 

1. Buy an avocado and remove the large seed from inside. Wash off any of the flesh but preserve the brown skin on the seed. Pat dry and set it aside to dry for a few days.
2. Avocado pits have tops and bottoms. Look for the end which is more pointed. You should also notice the base has a slightly flat shape compared to the top. This is crucial because if you place it the wrong way up, your tree will be doomed from the start.
3. Place the seed with the larger end at the bottom inside an AvoSeedo floater and float the container in a container of warm water at around 65 degrees. Change this frequently.
4. Within a few days a root will begin to form, and then from the top, the first signs of a tree will poke from the top.
5. When roots are almost filling the container, it is time to transplant to a pot.

Dwarfing Your Avocado Tree

This is the actual secret to growing avocado trees in hydroponic systems. Fully grown trees can grow up to 80ft high, but when you dwarf your tree, it can be a more manageable size while still providing fruits. To do this, restrictions on the tree growing space need to be imposed, the available water and also the nutrients provided must be strictly controlled.

These three elements will be a juggling act to let the tree grow as fast as it can while stunting its growth, and making sure it doesn’t die. If you are purchasing from a specialist tree dealer, don’t try to save time by buying a larger tree, the smaller, the better so you can shape its growth.

The growing pot at this stage should be as small as possible, but large enough to carry the plant for its first 12-months. Eighteen inches (45cm) is an ideal size to start, and then you will need to increase the size. This growing space will dictate the size of your final tree, so once the roots are well-formed, you can move to a five-gallon (20-25L) sized container. As time runs on, you might be able to go larger in pot size so your tree can reach its full potential while remaining small.

The containers should be filled with either perlite, vermiculite, or coco fiber. A flood and drain method will be the most effective because any growth of algae will be prevented. Another system used can be a drip irrigation system and would need three emitters per avocado tree.

With either method, the crucial part is preventing the root ball from drying out. Likewise, when you are transplanting to the growing pot, be careful not to damage any roots. Avocado likes to have their roots carefully tended to.

Pinching will be a necessary step to keep your tree fuller and shorter. The terminal bud needs to be pinched out and as a result, the buds which are dormant along the branch spring into life. These branches grow outward rather than upward, thus keeping the shorter height.

Even with a shorter height, the dwarfed plant will still be producing full-sized leaves. The final height of your tree will be around four to five feet in height.

Modifying Your Hydroponic Growing Setup for an Avocado Tree

Two things that need controlling are the acidity (pH) and the salt content in the growing medium and the nutrient mixture. For optimal growth a pH of between six and seven is ideal, but salt content needs to be as low as possible. Dwarfed avocado trees don’t take to higher levels of salt, and this is one reason growers like the flood and drain because it helps to keep salts to a minimum. You can learn how to build a flood and drain (also known as ebb and flow) system with our comprehensive guide.

In the early stages, your nutrient mix should be half strength and your pH levels controlled with a digital reader, our guide to measuring and controlling your pH may help here. Once your tree starts to get bigger and stronger, you can increase your nutrients to full strength.

Depending on the species of avocado, they might need a cold spell once they are at the fruiting stage. This can vary, and it will also affect how you control the temperature of your nutrient mix.

Although you can grow these trees indoors, the aim is to get fruit. Indoor trees might not give fruit, so this type of project is more suited to a greenhouse where you can control the temperatures and the humidity. One final thing to remember is, even with a tree that is much shorter than a wild-grown variety, it will need a form of secondary staking.

The hydroponic growing medium doesn’t have the same sort of support as the earth, and with the upper weight of the tree increasing, it can quickly force your growing pot to capsize.   

Related Questions

Does an avocado tree need full sun?

Because the trees herald from Mexico, they do prefer full sun, but they do need protection from the western sun over the first few years. Once they develop strong root structures and dense leaves to protect the bark, they become much better at resisting strong sun.

How often will an Avocado tree produce fruit?

A full-sized avocado tree can produce up to 300 fruit per tree when it reaches around seven years of age. They do sometimes have alternate bears and have a bumper crop one season, and a smaller crop the following season. Dwarf avocados might be different in volume due to their more diminutive stature.

Will my avocado produce fruit?

Trees that are sold from grafts produce fruit quicker than ones that are grown from seeds. Growing from seed could take an extra three or four years before they bear fruit if not longer. When grown from a graft, you might see the fruit after three to four years.