The most frequently cited plant-based repellents include the oil of lemon eucalyptus (OLE) and
oil of citronella.
The
oil of citronella, a fragrant grass of southern Asia, has long been used as an insect repellent and often is sold in candles that are burned on the patio in hopes of driving away mosquitoes in the evening.
The United States Environmental Protection Agency considers
oil of citronella as a biopesticide with a non-toxic mode of action (EPA 1993).
For mosquito repellent, some people were giving
oil of citronella a try, and for a general animal repellent, they turned to castor oil.
citronellol and geraniol (
oil of citronella and lily of the valley) and eugenol (oil of cloves) showed pronounced repelling effects.
An alternative is
oil of citronella or pennyroyal diluted in vegetable oil.
Mosquito can dies and coils containing
oil of citronella do exhibit repellent properties.
Other natural repellents can contain ingredients like neem and citrus oil, and mosquito candles and coils containing
oil of citronella do exhibit repellent properties.