Diatomaceous Earth also known as DE (food grade) is a naturally occurring, soft, siliceous sedimentary rock that is easily crumbled into a fine white powder. It is used as a soil conditioner, because like perlite, vermiculite, and expanded clay, it retains water and nutrients, while draining fast and freely, allowing high oxygen circulation within the growing medium.
Diatomaceous earth can have a significant beneficial impact on the physical, chemical and biological processes of soil, water and the growth of crops.
Diatomaceous earth is of value as an insecticide because of its abrasive properties. The fine powder adsorbs lipids from the waxy outer layer of the exoskeletons of many species of insects. this layer acts as a barrier that resists the loss of water vapour from the insect's body. Damaging the layer increases the evaporation of water from their bodies, so that they dehydrate and die.