Medium Diatomite (Diatomaceous Earth)

Diatomite is a porous rock that is made from fossilized remains of diatoms. It is high in silica, very porous and lightweight. Diatomite is very absorbant and has uneven shape and size which resists overcompaction. As reported in the September 2006 Issue of the AOS Orchids Magazine, diatomite absorbs salt and salt can be injurious to orchid roots. If diatomite is used, be aware that it will retain fertilizer salts and is reported to not respond to conventional leaching/rinsing techniques. If orchid mixes containing diatomite are re-used, we strongly recommend that the mix be thoroughly soaked and drained repeatedly (minimum of 3 times) to make sure salts from fertilizing are no longer embedded in the diatomite.

Test for salts before reusing. Some orchid mixes made by other companies are made with heavy concentrations of diatomite, but not mixes from rePotme.com. We have never used diatomite in our orchid mixes because we prefer to use ingredients that work for us and have established reputations as safe and healthy for orchids and other prized plants. Diatomite is also valuable for its ability to repel slugs and is suitable for use on orchid benches, humidity trays and the greenhouse floor.