One of the easiest and most popular growing mediums, expanded clay (also called LECA) is inert, reusable and pH neutral. It is commonly used for indoor plants and hydroponic systems, and it is clean and easy to handle.
Using expanded clay for hydroponic growing
Clay does not absorb water and is quite inert, which makes it a great choice for ebb and flow systems, where a tank of growing medium is filled and emptied on a constant cycle. It is also excellent in drip irrigation systems, where a steady trickle of water keeps roots fed, because it holds plants in place and gives roots plenty of space.
Using expanded clay for indoor plants
You can grow indoor plants hydroponically in expanded clay using a self-watering pot: one pot holds the clay balls and has drainage holes, and a second pot below holds a little water.
Using expanded clay with soil
Expanded clay can be used with soil as a drainage layer at the bottom of a pot, mixed through the soil to improve drainage, or crushed and mixed in.
