Diatomaceous Earth

By Sheena Adams | Image: iStockphoto

Made from fine-milled fossilized remains of prehistoric freshwater diatoms (microscopic algae), diatomaceous earth is effective in controlling aphids, cutworms, maggots, cabbageworms, silverfish, slugs, pill bugs, ants, fleas and lice. It will not harm earthworms (even if ingested), and is safe to use around household pets.

The talcum-like powder can be sprinkled around infected plants, mixed with water and sprayed on, or made into a paste and painted on. It consists mostly of silicon, with small amounts of iron, sodium and magnesium, trace elements and minerals. When working with it, always wear a dust mask, as it is a very fine powder and you do not want to inhale it. Be sure to keep pets away while using as they should not inhale it either.

The product's razor-sharp edges affect pests either internally or externally, resulting in death. Since pests are not able to develop a resistance to it, diatomaceous earth is a long-term, non-chemical pesticide.

You can find diatomaceous earth at garden centres, in seed catalogues or at feed stores.

Diatomaceous Stem Paste
250 mL (1 cup) diatomaceous earth
375 mL (11⁄2 cups) water

Mix diatomaceous earth and water. Using a paintbrush, apply the thick paste to the trunk of any tree infected by insects. Apply it at least 45 cm (11⁄2 ft.) up the trunk. Works well to keep ants and pill bugs at bay.