What Are LECA Balls and How Do They Help Plants?

LECA is an acronym that stands for "lightweight expanded clay aggregate." They are little balls of clay used in place of soil for houseplants and commonly used in hydroponic gardening. They are made from clay, brick dust, and waste from the mineral albite. Jasmine Jefferson, founder of Black Girls with Gardens and contributor at Plants.com, shared her knowledge of this growing medium to help you determine whether LECA balls would be a good idea for your houseplants.

How Are LECA Balls Made?

LECA balls are made when pre-treated clay is fired in a kiln at high temperatures and then cooled down. The man-made material is extremely porous and helps with aeration and drainage when used in combination with soil.

Can You Use LECA Balls for All Plants?

"It provides all that plants need to grow—water and oxygen," Jefferson says. "But each plant has unique water needs whether grown in soil or hydroponic systems."

When changing over to a LECA growing system, Jefferson says it's critical to immediately monitor and tailor each plant's individual watering and fertilizing needs. Not every plant will thrive in LECA and gardeners have varied experiences with different plants. The key is to experiment with growing your plants in LECA.

Plants That Thrive in LECA

Many houseplants will thrive in LECA, including monstera, orchids, and snake plants. Some drought-tolerant plants that do not mind roots on the dry side may do well in LECA since the balls dry out faster than soil. Try these plants with LECA:

• Philodendron
• Alocasia
• Jade
• Hoya
• ZZ plant
• Spider plant
• Begonia

When Not to Use LECA

Plants with sensitive roots, or those that can't tolerate standing moisture, or are very light or very heavy drinkers might not thrive in LECA and may do best in soil. Experiment, but be cautious, when using LECA with the following plants:

• Pothos
• Prayer plant
• Stromanthe 
• Elephant bush
• Ferns
• String of pearls
  

Pros and Cons of Using LECA

There are many benefits and drawbacks to using LECA when growing plants, all of which are entirely dependent on the type of plant itself.

Pros

• Provides the right amount of water: These baked clay balls soak up water, expand to retain water, and then release it for the plant's use a little at a time. "The LECA materials allow it to absorb water directly to the roots without suffocating them," Jefferson says. The clay balls prevent the plants from completely drying out but still provide proper drainage, which means less watering.
• Keeps pests away: "Houseplant pests such as aphids love to live in damp soil with rotting matter," Jefferson says. "LECA doesn't contain any live organisms, which means no pests." If you are tired of dealing with fungus gnats, LECA may be the solution.
• Requires less storage space: "It's ideal for an apartment or small-space gardeners," says Jefferson, "LECA requires less storage than traditional houseplant growing methods. No need to store big bags of soil."
• Less messy: "When watering a plant in the sink or its spot, soil spills on the floor or countertops, but that doesn't happen with LECA," Jefferson says. 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.
• Reusable: LECA balls are reusable. "You can use LECA balls over and over again, even forever if you maintain and clean it properly," Jefferson says. As your plant grows out of its container, 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. 

Cons

• Pricey: 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 but you don't need to replace LECA.
• Needs cleaning: New and used LECA needs to be washed to get rid of dust particles and little roots growing in and around the balls. You'll need to clean new balls out of the bag (soak for a few hours) and the LECA in your pots every week or two. Use water in a bin to swish and clean the balls (similar to cleaning rocks or beans) and dispose of the dirty water outdoors.
• Needs 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.
• Requires pH monitoring: You'll need a pH testing kit 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.
• Needs pots without drainage holes: LECA balls need a closed bottom vessel to soak up water so you will need new pots without any drainage holes. You'll then need to keep the container about a ⅓ of the way full of water to maintain a constant absorption rate.
  

Tips to Get Started With LECA

If you're planning to use LECA, Jefferson offers these tips to get started: 

• Choose younger plants: 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.
• Keep older plants in regular soil: The roots of houseplants grown in soil differ structurally from those that grow in water so the transition to LECA can be jarring, especially for older or larger plants. 
• Experiment with some 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 plants that aren't expensive or cherished. 
• Prep plants for transfer: When transferring a soil-based plant to LECA, always remove all traces of the potting soil from the roots to avoid any root rot problems.
• Mix with soil at your own risk: LECA is not typically mixed with soil though some gardeners swear by this method. The mix may damage your plant or help it thrive.
  
• Remember the fertilizer: 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.