Expanded Clay Aggregate
Definition - What does Expanded Clay Aggregate mean?
Expanded or expandable clay aggregate is a commonly used hydroponic grow medium. It is a lightweight aggregate that is heated in a kiln oven to a temperature of 2,910 degrees Fahrenheit (1,200 degrees Celsius). Once the aggregate is heated, it releases gases, which create small bubbles that make a honeycomb-like structure inside of the aggregate.
The movement of the kiln makes the aggregate form into a round shape. The round shapes of expandable clay vary in size. Expandable clay has become a popular growing medium in hydroponics and aquaponics because it secures roots and retains water. The clay has a neutral pH, which also makes mold and fungus less likely to grow.
MaximumYield explains Expanded Clay Aggregate
Expandable clay is often used in concrete blocks, concrete slabs, aquaponics, water treatment, hydroponics, and hydroculture. When used in hydroponic gardening, the expandable clay is considered to be a soilless growing medium. It can also be added to soil to improve drainage.
When added to soil the expanded clay helps the soil retain water during periods of drought. Expandable clay acts an in ideal root insulator when used in areas that frequently suffer freezing weather.
The use of expanded clay as a soil amendment is ideal to increase oxygen in the soil which promotes vigorous plant growth. When mixed into heavy soil, expanded clay improves the soil’s aeration potential and also increases drainage.
Expanded clay is also sometimes called Hydroton, clay pebbles, light expanded clay aggregate (LECA), or simple clay. It resembles brown pebbles. This grow medium can be rinsed and reused, making it a popular, economical choice. It's often paired with net pots or mesh pots, which holds the medium neatly in the system.