It seems like the latest buzzword among houseplant lovers is LECA. As I bounced through my numerous houseplant groups on Facebook, I kept seeing LECA pop up all over. So, what is it?
LECA is an acronym that stands for lightweight expanded clay aggregate. It is made up of little balls of clay—a growing medium—and used in place of soil. It is commonly used in hydroponic gardening.
How exactly do you plant anything with roots in small balls of clay? I've spent years writing about outdoor gardening and have never used anything but soil to grow plants. So I decided to seek out LECA experts to determine if these clay balls are worth the hype. Jas Jefferson of Black Girls with Gardens and contributor at Plants.com shared her knowledge of LECA with me.
The biggest question I had was, why replace your soil with LECA at all? The soil has nutrients and is biodegradable. Once you've exhausted your potting soil, you can toss it in the compost. What advantages does LECA have over something tried and true?
LECA Provides the Right Amount of Water
"It provides all plants need to—grow, water and oxygen," says Jefferson. "The LECA materials allow it to absorb water directly to the roots without suffocating them." The baked clay balls soak up water and expand.
"The clay retains the water and releases it for the plant's use a little at a time. The clay balls prevent the plants from completely drying out but still provide proper drainage, which means less watering—perfect for those who forget to water or are on vacation. "It's good for busy people," explains Jefferson, "you can add a little extra water, and the system stays moist longer."
LECA Keeps Pests at Bay
"Houseplant pests such as aphids love to live in damp soil with rotting matter," says Jefferson. "LECA doesn't contain any live organisms, which means no pests." This is the number one reason for the switch from what I witnessed in my houseplant groups. Plant parents were tired of dealing with fungus gnats and root rot, so they got rid of the soil and replanted their babies in LECA.
LECA Takes Up Less Storage Space
Although there's such a thing as "all-purpose" potting soil, not all plants love them. Currently, in my potting shed, I have about five different types of potting soil. The soil is specific for the types of plants I own. With LECA, there's no need to purchase different soil for your orchids or succulents—it works for virtually every kind of plant. "It's ideal for an apartment or small-space gardeners," says Jefferson, "because it requires less storage than traditional houseplant growing methods. No need to store big bags of soil."
LECA Is Less Messy
"We've all done it," says Jefferson, "When watering a plant in the sink or its spot, soil spills on the floor or countertops—that doesn't happen with LECA." The main thing you have to deal with LECA is the dust when you first open the bag. After the initial soak, the clay balls are dust-free and ready to pot up.
LECA Is Reusable
Soil does not stay full of nutrients forever. Whenever you repot a plant, you need to replace the soil. "You can use LECA balls over and over again," says Jefferson, "even forever if you maintain and clean it properly." As your plant grows out of their containers, all you need to do is transfer it and the LECA to the new pot. If you are reusing the clay balls for another plant, it needs to be washed thoroughly first.
The Cons of Using LECA
LECA may seem like a miracle growing medium, but it does have its cons.
It Can Be Pricey to Transition
For one, it's expensive—three to four times more costly than soil. The initial cost to convert all your plants to a LECA medium isn't cheap.
You Have to Buy Fertilizer
Besides the high start-up cost, you need to purchase hydroponics fertilizer or liquid fertilizer specific to your plants. All LECA does is take care of watering your plants; it does not provide any nutrients.
You May Have to Buy New Pots and Other Tools
You will also need to get pots without drainage holes and other gear such as pH monitors. For LECA to soak up water, it needs a closed bottom vessel. You keep the container about a ⅓ the way full of water to maintain a constant absorption. You will also need to monitor the water quality to ensure that it's holding the right pH level. The pH level is crucial because it affects nutrient availability for your growing plants.
Plants That Thrive in LECA
The good news is that most houseplants thrive in LECA, including monstera, orchids, and snake plants. "Each plant has unique water needs whether grown in soil or hydroponic systems," says Jefferson, "so when changing over to a LECA growing system, you'll need to calibrate your watering and fertilizing based on the tailored needs of your plants."
Tips to Get Started With LECA
Now that you know all the pros and cons of LECA, are you ready to take the plunge? Jefferson offers these tips to get started:
- When selecting plants to transition from soil to LECA, it's helpful for beginners to start off using younger plants with less dense root systems or to use cuttings propagated in water.
- The roots of houseplants grown in soil differ structurally from those that grow in water so that the transition can be jarring, especially for older or larger plants.
- As with any significant change to your houseplants, there's always some risk to the plant. While you're building up your LECA skills, start with those that aren't expensive or cherished plants.
- You'll need new tools (a pH testing kit and new pots, among other items) to get started, but these can be easily found online or at select local garden retailers.
- It's important to remember that LECA provides water but not nutrients, so growing plants in this medium will require periodic applications of hydroponics fertilizer.
- These needs vary, so put a little time into research, so your particular plant will ensure it will thrive in its new environment.