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Hydroponic Clay balls

Clay balls or Hydroton grow rocks, or expanded clay pellets, also referred to as leca clay, are one of the most helpful and versatile growing media to any traditional and hydroponic grower.

They’ve gained popularity over the last ten years for their porous shape. With these pores throughout each ball, the pellets make it easy to support a steady distribution of nutrients, oxygen, and water around the roots of various plants.

If you’re looking for a quality Clay balls product/brand on the market, here’s our top pick

What is Clay balls / Hydroton / Expanded Clay Pellets?

Expanded clay pellets (Hydroton) are made by heating the clay to over 2,000 degrees Fahrenheit. The process is done in a rotary kiln. As the balls heat up, they fill with bubbles and form into small marble-sized units.While the clay can be used on its own for growing plants, it can also be mixed with soil and other growing media. Hydroton is used widely in hydroponics and aquaponics.

Benefits of Clay balls Over Other Sources

There are many reasons that you may gravitate towards the use of extended clay pellets for horticulture growing.


While expanded clay pellets last for a long time, it won’t actually nourish the plant. They have no nutritional value and are primarily meant to use as vessels for the other food provided to your plant. For this reason, they help to keep insects and bacteria away from the plant during growth.

Water drainage

The biggest appeal seems to be the way that it helps to drain excess water, though they also keep enough nourishment for constant delivery of it to the roots.

pH neutral

This will bring no effect on the current soil used in the garden. You can combine it with any plant solutions and foundation you need for your garden, without worrying its impact. These pellets are an inexpensive method of making nourishment go a long way.

Easy for harvest and transplantation

Because hydroton is a form of pellets, it does not stick. You will not face much nuisance when taking the plants/seedlings completely from the grow pots.

Downsides of Hydroton

Costly for large growers

Hydroton is such a very easy-to-use material for hobbyists and small growers, but it is not

cost-effective for commercial productions or large-scale growing.

Drainage issue

Drainage issueThe most discernible advantage of hydrotongrow rocks is also its own cons. Because it drains significantly well, this material can dry out very quickly. Not a big concern, but just keep that in mind if your plants do not have a consistent flow of water and nutrients.

Dust from the clay

Unless you clean and completely soak these pellets, dust from this material can float. And there’re chances it blocks your system drain lines.

Hydroton and Hydroponics

Without doubt, hydrotonis one of the most popular growing media chosen by hydroponic and aquaponic growers. Because it’s sterile, lightweight, easy to harvest, and transplant, it can be used in almost any hydroponic system – wicking, deep water culture, ebb & flow, etc.

One caution to work with hydroton is that because it does not have a great water holding capacity, it’s better that you have a hydroponic system that irrigates/waters regularly. This is really worth thinking when you grow water-craving plants like lettuces using hydroton as the main growing medium.

Another approach is to crush the pellets for better drainage. But this comes with a con that the medium can be flown away and block the system in a water-heavy system like the Ebb & Flow.

How to Correctly Prepare Hydroton / Clay Pellets for Use

Before putting the expanded clay pellets into a garden, you need to take the time to rinse and soak them, getting rid of any debris or dust that resides in the pores. You can use a bucket of water to moisten the pellets though you may need to rinse again.

To infuse them with nutrients, add your preferred growing solution before placing them in the garden or pot. Only use about 25% of what you normally use, since it’s already going to be concentrated while it soaks into the pellets.

Some resources suggest that you allow the expanded clay pellets to soak for at least six hours, though soaking for up to 24 hours will yield the best results. You should notice how much heavier the pellets are after the soaking.


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