LECA balls work by absorbing water and then making that stored water available to plant roots.
LECA, which stands for Lightweight Expanded Clay Aggregate, are essentially small balls made from clay that has been baked at high temperatures. This baking process causes the clay to expand and become porous. It's these tiny pores and the overall structure of the balls that allow them to function effectively in hydroponic or semi-hydroponic plant setups.
The Mechanism: Absorption and Release
Here's a breakdown of how LECA balls operate:
- Water Absorption: When LECA balls are exposed to water, they soak up some of the liquid into their porous structure. Think of them like tiny sponges made of baked clay.
- Slight Expansion: As they absorb water, they will expand slightly.
- Water Storage: The water is held within the internal pores and on the surface of the balls. This stored water is crucial because it provides a reservoir for plant hydration.
- Availability to Plants: Plant roots growing among the LECA balls can access this stored water. The roots absorb the water they need from the balls and the surrounding humidity created by the LECA retaining moisture.
LECA's Role in Plant Growth
Unlike traditional soil, LECA serves primarily as a medium for support and hydration.
- Physical Support: The balls provide a stable structure for the plant's roots to anchor themselves.
- Water Delivery: Their main function is to hold and regulate the delivery of water to the roots. This can help prevent both overwatering (as excess water drains away) and underwatering (as the balls retain moisture).
- Aeration: The gaps between the individual LECA balls allow for excellent airflow to the roots, which is vital for preventing root rot and promoting healthy growth.
LECA vs. Soil: A Key Difference
It's important to note a significant difference between LECA and soil based growing:
| Feature | LECA Balls | Soil |
|---|---|---|
| Material | Baked Clay | Organic Matter & Minerals |
| Water Role | Absorb, store, and release for plants | Holds water, provides humidity |
| Nutrients | Do not contain any nutrients | Contains varying levels of nutrients |
| Structure | Porous balls | Varied, includes fine particles |
Since LECA doesn't contain any nutrients, plants grown in LECA systems must receive their required minerals from a water-soluble fertilizer added to the water reservoir.
In essence, LECA balls work by acting as a porous, inert medium that efficiently absorbs and provides water to plant roots while ensuring good aeration, differing significantly from nutrient-rich soil.
