Gardeners are always on the lookout for natural products that can keep their garden free from pests. Diatomaceous earth is a naturally occurring pesticide that seems almost too good to be true: it repels pests both in your garden and your home and won’t harm your family or your pets.

Let’s take a closer look at what diatomaceous earth is and how it can benefit your garden.

What is diatomaceous earth?

Diatomaceous earth, or DE, is comprised of diatoms, the fossilized remains of tiny aquatic organisms – microscopic, single-celled algae. The organisms’ skeletons are made from silica, making the areas where their fossils are found rich areas for silica mining. These shells are like snowflakes, unique and even artistic in shape. Diatomite forms when amorphous silica accumulates in the sediment of lakes, rivers and oceans.

What are some uses of diatomaceous earth?

Diatomite is found in a variety of uses, including in cat litter, as an agricultural food additive, and as a product. Products containing DE are usually dusts, but also include wettable powders and pressurized liquids.

Products using DE protects against bedbugs, cockroaches, fleas, ticks, spiders and other bugs. DE is found in beauty and skincare products and toothpaste.

Food grade DE is purified before use. It is used to prevent caking in livestock feed, and as a clarifier in beer and wine.

How does DE function as a pesticide?

DE is not poisonous, and does not have to be ingested to control bugs. When exposed, DE powder absorbs the oils and fats from the insect’s exoskeleton. DE has sharp edges, which pierces the insect and boosts the product’s effectiveness. DE remains effective as long as it remains dry.

How does DE affect soil?

Silicon is a major component of DE. Silicon is also the second most common element in soil, comprising 26 percent of the Earth’s crust by weight. Silicon is also common in plants and plays an important role in their development.

DE is not degraded by light or microbes, and does not emit vapors. It does not dissolve in water.

The ocean contains large quantities of DE; some animals even use it to build their exoskeletons.

Are there any health concerns?

Health Canada classifies diatomaceous earth as a natural health product (NHP). DE has not been shown to harm fish, birds or other wildlife. If used properly, it won’t harm humans, pets or the environment.

Still, humans can be harmed by exposure to DE if they inhale the dust, ingest it or get it on their skin. This is why proper application is important to avoid exposure. If you are exposed to DE, contact your local Poison Centre.

Symptoms of DE exposure include irritation of the nose and nasal passages if inhaled, and skin irritation and dryness if touched. As a dust, it can also be irritating to the eyes. If ingested, it will not be absorbed by the body and will leave quickly. Studies have not found DE exposure to cause cancer in animals.

This summer, the Canadian Food Inspection Agency (CFIA) is making regulatory changes that could prevent the export of DE to the United States. CFIA issued a voluntary recall of Absorbent Products’ Red Lake Earth anti-caking agent for livestock feed, but the product continued export to the US with the Food & Drug Administration’s approval. CFIA plans to enforce rules on exports in July, which may force the company to relocate.

To learn more about diatomaceous earth, contact one of the Soil Advocates Team at or 289-221-0164.

Join Our Growing Percolator Community
...and bubble to the top

We respect & value your privacy