Diatomaceous Earth are natural occurring remains/fossils of fresh water sediment. It typically comes as a fine off-white powder and is composed of the shells of microscopic prehistoric diatoms and phytoplankton. Over many years, these diatoms accumulated in the sediment of rivers, streams, and lakes.

Diatomaceous Earth (often shortened to DE) has a very high silica content. In fact, about one quarter of the Earth’s crust by weight is silica. You may know silica in some of its many other forms including glass, sand, clay, asbestos, and mica.

There are a variety of uses when it comes to DE including skin care products, toothpastes, foods, beverages, paints, water filters, and medicines. In our tip, we’ll be focusing on its use in agriculture and specifically pest control.

DE can be used against a wide range of insects including bed bugs, spiders, cockroaches, crickets, fleas, and ticks. It works by causing them to dry out by both absorbing the fats and oils from an insects exoskeleton as well as using its sharp edges to puncture the skin. Diatomaceous Earth works best when it is kept dry and undisturbed.

Other agricultural uses of DE include as an anticaking agent in grain storage and as a growing medium (especially in bonsai)

It is not poisonous, non toxic, and very hard. Always follow the labels and read the instructions of any product you purchase. Keep in mind that there are some products that are labeled as food grade (and safe to ingest)

Diatomacoues Earth can be purchased from many garden centers and online.

Cover Image by James St. John, used under its Creative Commons license.

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