It’s an unavoidable fact for every gardener: insects invade the healthiest of gardens at any time during the year. Some of these bugs and worms are beneficial to the garden; bees help to pollinate plants and worms aerate the soil and help to make it fertile. Others can be destructive to your plants. How can you get rid of the bugs ruining your garden without harming the delicate ecosystem that supports it?
Green solutions are an excellent way to manage the health of your garden and keep the nasty bugs in check. They’re also an environmentally responsible way of treating a pest problem. Chemical-based pesticides commonly use toxic chemicals to kill the bugs including metals and arsenates, and can frequently be harmful to pets and children. The overwhelming majority of pesticides end up somewhere other than their target species, and as such are a source of pollution.
What is Diatomaceous Earth?
Diatomaceous earth, also known as D.E. or diatomite, consists of the fossilised remains of diatoms, a kind of algae. It is sold as a soft sedimentary rock that is easily crumbled into a fine powder that can be spread on the garden bed as well as through the house.
Diatomaceous earth has a number of different uses; it is used as a pesticide because of its abrasive and physico-sorptive properties. The fine particles of D.E. get stuck between the joints of an insect and begin to cut into the shell, killing it. Diatomaceous earth also absorbs the lipids from an insect’s exoskeleton, causing them to dehydrate and die.
When Should I Use Diatomaceous Earth?
In the home, D.E. can be used with great effect on ant, cockroach and flea infestations. In the garden, the substance can be used to kill ants, beetles, aphids and snails. Anything with an exoskeleton is vulnerable; it is also effective against gastropods like slugs, although in humid environments the efficacy is limited.
D.E. is often favoured because it is safe to use, 100% natural, harmless to mammals and can be used in many different ways. It is widely used in grain storage to prevent infestations and food-grade D.E. can be consumed by humans without ill effect.
How Do I Use Diatomaceous Earth?
You’ll need to find horticultural-grade D.E., which should be easy – your local garden centre will surely have it, but if you have any problems you can find an online retailer. It’s a simple application process. All you need to do is wait until you have a relatively dry period and sprinkle the D.E. over the soil bed and dust the plants. If it rains, reapply the D.E. as soon as the ground dries out.
Although D.E. is safe on earthworms, it will kill bees if they come into contact with it. You can take reasonable precautions by not applying the powder to any flowering plants and keeping a source of clean water for the bees to drink nearby so they won’t drink from the earth.
Kahmen Lee is a freelance writer who specialises in green household and garden solutions. In her spare time, she writes for Admiral Pest.