Diatomaceous Earth is a fine powder made of crushed microscopic organisms called, “diatoms,” which were hard-shelled algae living millions of years ago. It’s abrasive and absorbent, and that’s the mechanics of how it works. When pests walk through the Diatomaceous Earth, it causes tiny cuts on the insect’s exoskeleton, and then absorbs fats and oils, eventually causing it to dry out and perish. It is important to note that while wet, Diatomaceous Earth will not have the same effectiveness as when it is dry. High humidity and moisture levels will impede the ability to kill bugs, so I use this more on Succulents and Cacti than on Aroids or other tropical plants. After drying out, it will regain effectiveness.
It can be applied topically, onto affected plants, or mixed into soil. The pictured brand happens to come with a small duster that can be used for an even distribution of the powder. If using a duster, it is recommended to use a mask to avoid inhaling the dust, as it can cause irritation to the nose, throat, and lungs. When mixing into soil, try to distribute as evenly as possible.