LECA stands for Lightweight Expanded Clay Aggregate, which is a lightweight aggregate made by heating clay to around 1,200 °C in a rotary kiln. The yielding gases expand the clay by thousands of small bubbles forming during heating producing a honeycomb structure. LECA is a versatile material and is utilized in an increasing number of applications. In the construction industry, it is used extensively in the production of lightweight concrete, blocks, and precast or incast structural elements (panels, partitions, bricks, and light tiles) . LECA is also used in structural backfill against foundations, retaining walls, bridge abutments, etc. It can reduce earth pressure by 75% compared with conventional materials and also increases ground stability while reducing settlement and land deformation. LECA can drain the surface water and groundwater to control groundwater.

LECA is also used as a growing medium for plants. It is a collection of baked clay balls that expand when soaked in water. Unlike soil, LECA does not contain any nutrients, but it can be used as a medium for plants to grow in. It makes watering plants much easier, reduces the risks of getting pests, and allows for easy checking on plants. LECA provides space for oxygen to flow through to the plants roots, which is essential for plant growth. It also provides the perfect balance of hydration by slowly diffusing water into the roots of a plant. LECA is ideal for plants that would usually grow in an environment where their roots get lots of airflow, like tropical epiphytic plants such as Hoyas, Philodendrons, and Monsteras. However, plants with sensitive roots, those that cant tolerate standing moisture, or are very light or very heavy drinkers might not thrive in LECA and may do best in soil.

In summary, LECA is a versatile material used in construction and as a growing medium for plants. It is a collection of baked clay balls that expand when soaked in water and provides space for oxygen to flow through to the plants roots. LECA is ideal for plants that would usually grow in an environment where their roots get lots of airflow, but it may not be suitable for all plants.