Diatomaceous Earth is a type of algae, presented as a naturally occurring soft rock that consists of the remains of diatoms. It has been used by many growers because it is a fantastic insecticide, capable of preventing and eradicating most pests that you will encounter.
The powder is very abrasive, this will cut and rip some pests apart when they move through or over it. It also causes them to dehydrate by damaging the outer layer of their exoskeletons causing the water to evaporate from their bodies. This incredible compound is can be applied to your plants in a number of ways and is completely safe to use, causing absolutely no harm.
You can apply the powder as a foliar product, for pests which are located on the plants themselves. You can squeeze the bottle over the plants, resulting in a fine mist falling onto the leaves.
You may also apply a fine layer to the top of the growing media. Pests such as Fungus Gnats will be unable to lay their eggs as they cannot penetrate the powder. If you already have larvae present in your pots, the powder will kill them and if it does not, it will kill the larvae when they hatch and try to fly from the medium later on in life.