If you want to go organic try diatomaceous earth. You can buy it at most good feed stores.
What Is Diatomaceous Earth?
Diatomaceous earth is a naturally occurring sand extracted from the earth.
It consists of microscopic skeletons of algae — known as diatoms — that have fossilized over millions of years (
1).
There are two main types of diatomaceous earth: food grade, which is suitable for consumption, and filter grade, which is inedible but has many industrial uses.
The diatoms in diatomaceous earth are largely made up of a chemical compound called silica.
Silica is commonly found in nature as a component of everything from sand and rocks to plants and humans. However, diatomaceous earth is a concentrated source of silica, which makes it unique (
2Trusted Source).
Commercially available diatomaceous earth is said to contain 80–90% silica, several other trace minerals, and small amounts of iron oxide (rust) (
1).
Diatomaceous Earth as an Insecticide
Food grade diatomaceous earth is often used as an
insecticide.
When it comes in contact with an insect, the silica removes the waxy outer coating from the insect's exoskeleton.
Without this coating, the insect cannot retain water and dies of
dehydration (
5,
6Trusted Source).
Some farmers believe that adding diatomaceous earth to livestock feed kills internal worms and parasites through similar mechanisms, but this use remains unproven (
7).
