Chiggers live primarily outdoors, but they can migrate indoors as well. Wherever they are, they're incredibly irritating to humans due to their itch-inducing bites. They hang out in sensitive areas, like ankles and the backs of knees, where the skin bends more frequently, and use their saliva to liquefy human tissue and use their hosts as a mobile feast. Diatomaceous earth is a child- and pet-friendly way to eliminate them from the home and garden.
Chiggers are the juvenile form of tiny, red-colored mites from the family Trombiculidae. They are closely related to fleas and ticks and live in North and South America, Europe, Asia and Australia, as well as much of Africa. Though they do not carry any major diseases, the bites can cause an allergic reaction and are very annoying and unpleasant. Chiggers latch onto a host and remain for three to four days unless they are removed by soap and water or bug spray. To prevent their return, or get rid of a chigger infestation, diatomaceous earth is a natural solution with little environmental impact.
Diatomite, commonly called diatomaceous earth, has many uses in addition to pest control, including filtration, insulation and as pet litter and spill absorber. Made up of fossilized diatoms, it is incredibly useful for killing insects. The waxy coating on insects' exoskeletons is absorbed and scratched when the insect comes in contact with diatomaceous earth, which also damages their shells. The substance is generally harmless to humans and pets.
Diatomaceous earth can be sprinkled or dusted across a lawn to get rid of chiggers. Diatomaceous earth is also effective in the control of cockroaches, fleas and ticks. Garden supply stores sell diatomite dusters of various types. A wide application is best, though you may also use a garden syringe to pinpoint certain areas during application.
If chiggers have found their way inside your home, consider dusting diatomaceous earth around doors, windows and any other entryways to keep more from wandering in. Soft surfaces such as couches may also benefit from a light dusting, if it seems chiggers have taken up residence.