LECA (Light Expanded Clay Aggregate).

This free-draining medium is manufactured by mixing sodium with clay and firing in a rotary kiln to burn off the sodium, forming round pellets of various sizes, each pellet having ‘honeycomb’ spaces inside. These spaces allow nutrients to be taken up by the pellet and released to the plant gradually. They also allow oxygen to reach the roots of the plants. This is of paramount importance in hydroponics.

We stock various different sizes of Leca. 8 – 16 mm expanded clay balls work well for larger net pots and Dutch buckets, while the smaller 2 – 10 mm expanded clay balls work best for smaller sized net pots, eg. 50 mm, 75 mm and even 200 ml net pots. 8 -10 mm Leca is also available and can be used as desired, most probably for medium to larger sized net pots and also for grow beds, Dutch buckets, etc.

The lightweight roundish clay balls of various sizes make for a great hydroponic growing substrate. It’s the perfect media choice for ebb and flow and drain to waste. Water flows between the pebbles quickly, supplying the roots with nutrients, yet allowing the roots to stay oxygenated. Roots and plants develop healthy and vibrant.

With the advantage of light weight, high permeability, high durability and excellent sound and thermal insulating properties, LECA is a good ‘all round’ aggregate for use in an a variety of applications.

NB: Product needs to be flushed/rinsed before use. Shape and colour may vary according to availability.


Leca is a Lightweight Expanded Clay, formed by the heating and firing of clay in a rotary kiln, at temperatures of up to 1150°C. The process transforms the clay into various lightweight ceramic granules, which have a hard ceramic shell and a porous core.

Intact Granules

  • Higher insulation (more closed pores)
  • Better drainage (bigger gaps between granules)

Fragmented Granules

  • Better moisture retention (more open pores)
  • Better soil aeration (promotes healthy bacteria)
  • Increases root biomass (sharp edges split and induce exponential root development)

Benefits of Leca

Manufactured to relevant ISO standards, Leca is consistent in nature:

  • pH neutral
  • stable & durable
  • anti-fungal
  • resistant to insects