Growth Medium 101: Soilless media- LECA - Part 2 LECA

Have you ever struggled growing plants in regular potting soil? Are you a plant parent that is often out of town and worry about who's going to water your plants? Or, maybe, you just can't seem to keep up with watering your plants, no matter what you do. Well, maybe LECA is for you!

LECA has taken the plant world by storm and seems to be one of the hottest buzzwords in plant groups and plant articles all over the internet. LECA stands for Lightweight Expanded Clay Aggregate and is a way to hydroponically grow your plants. It's, also, called the 'forbidden cereal' due to its appearance looking exactly like Cocoa Puffs.

Growing plants in LECA is designed to bring more oxygen to the plant's roots and allow them to absorb as much water and nutrients as needed. These clay pebbles are the perfect option for a soilless growing medium.

Plant collection
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Guide to Growing Houseplants in LECA

Why is LECA Useful For Growing Plants?

LECA, sometimes called hydroton, is made from clay and is heated in a kiln at high temperatures. This high heat leaves the clay pebbles with a honey comb like structure with lots of air pockets inside - almost like a hard foam. These air pockets allow plants to absorb moisture directly and they only take up what's needed.

Once the water is gone from your plants in LECA, you know the excess water was either absorbed by the LECA pebbles or the plant's roots. Unlike soil, you don't have to make sure you consistently water at the right time to prevent any root rot or even dry rot.

How to Choose the Right LECA for Your Plant

LECA pebbles vary from brand to brand. They can vary in size, smoothness and even porosity. Some things to note about the different types of LECA balls:

Size

The size of the LECA pebbles will determine how much room your plant's roots have to grow. Larger clay balls will allow your plants roots to receive more oxygen. However, larger LECA balls provide less structural support because it packs looser.

Texture

Smoother LECA is much like large LECA pebbles. It helps with faster root growth and better air flow but packs loose. Therefore, supporting the plant by its roots will be difficult, especially when first repotting the plant.

Houseplant soil
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Rougher LECA balls will be more dense and provide plant roots to properly attach. However, less oxygen is able to flow and repotting might be more difficult. The plant roots may attach strongly to the clay balls and cause too much disturbance in the roots when you want to do a quick, simple repot.

Porosity

As mentioned earlier, the porosity of clay balls will vary by brand. But, in short, the more porous LECA is the more absorbent it is. More porous LECA helps wick up moisture faster.

Potting your plants in LECA

Preparing LECA for the first time

Prior to planting your plants in LECA, it's important to flush the LECA balls. The clay balls are covered in clay dust which isn't ideal for indoor plants. Follow these steps to make your clay balls ready for house plants.

Wash the LECA in water

It's important to wash the clay balls in water in a bucket that's not in a bathtub or sink. The clay balls will be covered in clay dust that will clog your drain once mixed with water. Simply use a bucket, fill with water and wash them until the water isn't cloudy anymore. This process may take several cycles before you notice the water is no longer cloudy.

Once this process is done, it's recommended to soak the clay pallets for up to 24 hours. This helps the LECA balls absorb water more efficiently when potted with a plant.

Drying LECA clay balls

After rinsing you have two options; plant up your house plants right away or store the leca balls for later use. Make sure to always lay the clay balls out to air dry for a couple days before you close them up and store them. Storing wet baked clay balls can cause algae growth or unwanted visitors.

These simple steps will set your plants up for success when growing houseplants in leca medium.

Prepping your plants for LECA

Moving plants from soil to LECA, can be an easy task but needs to be done correctly to prevent the plant from going through transfer shock. Younger plants have a higher success rate and it easier to transfer.

First, you will need to gently remove the plant from the soil, dry soil would be easier. Make sure all the big chunks of soil are off the roots the you'll need to rinse any all dirt debris you see on the plant roots. Make sure to be gentle enough to not break any roots.

Next, it's recommended to let the plant roots air dry for a short period of time. To ensure any extra pieces will dry up and fall off but will also make transfer period easier. The plant roots will be slightly dehydrated and eager to absorb water when potted in the lightweight expanded clay aggregate. After this, your plants will be ready to be placed in the baked clay balls.

Potting up your plants in LECA

Now that the plant has been properly rinsed and is no longer in soil, you can finally pot it in LECA. You will need two separate pots; one net pot that's used to hold the plant and the LECA balls and an outer pot, a cache pot, with no drainage holes. The net pot will be placed inside the outer pot and the outer pot will hold the water. The water level must only fill about 1/4 of the cache pot. The plant roots can't touch the water or this will lead to root rot.

After planting, you could follow up with a hydroponics fertilizer that is geared towards root growth. This will help with the transition process and can help avoid transfer shock. Keep the plant in the same growing condition as it was previously, and prevent any drastic changes in temperature or lighting.

During this period, your plant may look a little rough. The plant will need to grow water roots and shed the soil roots. Soil roots have more hair like structures to help absorb oxygen from the soil where as water roots are more smooth and made to absorb oxygen from from water. Be sure to regularly check the roots, and cut off any bits that turn mushy. If you notice too much root rot, cut the rotting parts and rinse the plant roots in a solution with 1 part water and 1 part hydrogen peroxide.

Using fertilizer with LECA

LECA clay pellets have no nutrients so it's crucial that you have a good liquid fertilizer so your plants thrive. The most common hydroponics fertilizer use by plant owners is Fox Farm hydroponics fertilizer trio or Dynagrow. You will need to mix the solution in a separate container and regularly add the solution to your water. Read more about fertilizers in our earlier blog post.

Flushing LECA plants

You'll need to flush your LECA plants on a monthly basis. Minerals will build up over time around the plant roots and LECA and could mess up the way your plant absorbs water and nutrients. To flush the LECA, simply hold the plant and net pot under running water for a few minutes. Follow up with fresh water and nutrient solution.

ZZ Plant roots
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How to propagate plants using LECA

While, I personally prefer to grow my plants in soil over LECA, propagating plants in LECA is one of the best methods. And propagating a fresh cutting in LECA is the only way to prevent your plant from going through a transition period since it'll be in LECA from the start.

You just need to take your unrooted cutting and put it in a net pot with LECA. Over the course of a few weeks, the plant will absorb any need water and you'll see roots in no time.

LINK to the propagation methods article

Don't forget to give these plants the support if needed. We have lots of staked as well as wall mounted trellises to choose from.