D
erived from small pieces of clay processed at
extremely high temperatures, expanded clay
pebbles have become a go-to grow medium
for many hydro growers over the last 10 years, offering
numerous benefits to gardeners when used properly.
Expanded clay pebbles resemble oddly shaped,
semi-rounded pieces of clay-colored popcorn.
The high-heat popping during the manufacturing
process gives the medium its large, airy macro-pores
(spaces between each piece of expanded clay), in
addition to its micro-pores, which are contained
within each piece of expanded clay. The medium
provides plants with hefty amounts of oxygen for
fast-growing roots, and it holds
enough moisture within
its micro-pores to allow
for healthy water and
nutrient retention
from the roots all the
way to the top nodes.
This spacing also allows
for excellent
drainage when
using top drip
or ebb and
flow growing
methods while
still allowing
roots to draw
water out of the
clay’s pores.
“Expanded clay pebbles
resemble oddly shaped,
semi-rounded pieces of claycolored popcorn.”
Throughout my years of tinkering with and
exploring hydroponics, I have found myself using
this medium time and time again. For me it took
trial, error, failure and eventual success before I
came to fully understand the potentials of using
expanded clay. Here’s what I’ve learned so far.
Maximum Yield USA | April 2015
145