Reusing coffee grounds offers benefits from fertilising plants to repelling mosquitoes. Coffee grounds have a smouldering effect after you light them that keeps insects at bay. Also, reusing coffee grounds saves money. Some people use coffee grounds in a compost pile to feed worms and keep other insects away, according to the U.S. Environmental Protection Agency (EPA). Mosquitoes, like other insects, are repelled by the odour created from the coffee grounds burning.
Remove the coffee grounds from your coffeemaker and put them in an aluminium foil pie plate. Place them in a cool, dry area until they are completely dry.
Place the foil plate with the coffee grounds on a level surface, such as a table, outdoors. Make sure no animals or children have access to the area.
Add a few drops of barbecue lighter fluid to the coffee grounds. Do not saturate the grounds--this makes them burn too quickly.
Light the fluid with a long match to avoid getting burnt. Then, allow the lighter fluid to burn off until the coffee grounds start burning and smoking.
Smother the fire with a large, damp towel or cloth by placing it over the top of the plate. The coffee grounds should continue to smoke and smoulder. The smoke from the coffee grounds repels the mosquitoes.
Only burn coffee grounds to repel mosquitoes outside where there is adequate ventilation.
Exercise caution when dealing with fire and flammable fluids.