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Free Hydroponic Growing Medium: Pumice (Pinagbistayan)

Corn kernel sized light colored rocks held with two hands.

Pumice is one of the best hydroponic growing medium out there. Pumice is light, inert and porous. These properties makes pumice perfect for hydroponics as these provides high drainage, aeration and promotes healthy root growth. Compared to other hydroponic growing medium like hydroton (LECA) and perlite, pumice is naturally occurring and is thus eco-friendly.

About Pumice.

Pumice is a type of volcanic rock that has a foamy appearance. This is the result of the rapid expansion of gases when material gets ejected from volcanoes and rapidly cools.

White porous stones.
Close up picture of pumice stones.

Pumice is a major component of lahar and is plentiful in areas around Mount Pinatubo. Mount Pinatubo ejected millions of tons of pumice when it erupted in 1991. Since then these aggregates has been mined and used as construction materials.

Pumice in construction.

Construction sand sourced from areas affected by the Mount Pinatubo eruption are composed of pumice. Before use, construction sand is generally sieved by construction workers before it is mixed with concrete. The remaining material called “pinagbistayan” (or pinagsaligsigan?) is often just discarded.

Small light colored rocks of various sizes.

Pumice for Free

One can find pinagbistayan in construction areas. If the construction sand being used in these construction is sourced from areas around Mount Pinatubo affected areas then the aggregates left over when the construction sand is sieved is pumice.

Be sure to checkout those construction areas for very useful stuff like pumice.

Can’t find pumice anywhere? Buy pumice from our shop!

Happy growing!