Lavender essential oil is distilled from the flowers of English lavender (Lavandula angustifolia syn. Lavandula officinalis), a perennial member of the mint family native to the mountainous regions of the Mediterranean, and grown as an ornamental specimen in U.S. Department of Agriculture plant hardiness zones 5 through 8. The oil is widely used in the cosmetic, fragrance, and food and beverage industries. Lavender oil is also reputed to naturally repel certain pests, including mosquitoes.
Lavender Oil Characteristics
Lavender essential oil is highly aromatic and also highly concentrated, consisting of the "essential" components of the plant's volatile oils that naturally protect it from predatory insects, wildlife and diseases. Because these and other chemicals in the oil are affected by different methods of processing, oil produced by steam distillation is preferred over those distilled by water or chemical solvent. Also, be aware that oils labeled as "fragrance oil" are likely adulterated with synthetic ingredients. Instead, look for "100 percent pure" or "certified organic" lavender essential oil.
Lavender oil contains up to 25 percent linalool, a terpenoid alcohol that contributes to its fruity fragrance. According to the U.S. Environmental Protection Agency, this agent is an active ingredient in more than a dozen registered products used to control mosquitoes outside.
Effectiveness Against Mosquitoes
Studies show that linalool has the same effect on mosquito olfactory receptors as diethyltoluamide, a chemical used in many conventional mosquito repellents more commonly known as DEET. In one 2009 study published in the Journal of Vector Ecology, the use of linalool diffusers had a mosquito repellency rate of 93 percent indoors and 58 percent outdoors. However, the same study also found geraniol, the active compound in geranium oil, more effective at repelling mosquitoes than linalool or even citronella.
Therefore, although lavender oil does repel mosquitoes, its effectiveness may be enhanced when used in combination with other oils. Colorado State University recommends the use of lavender oil with cinnamon oil, tea tree oil or citronella oil to help keep mosquitoes away when outdoors.
As with all essential oils, lavender oil should be diluted with a carrier oil, such as sweet almond oil or jojoba oil, before using on the skin to avoid irritation. As a general guideline, a basic skin oil consists of 1 to 4 drops of essential oil for each tablespoon of carrier oil.
Another way to use lavender oil to counter mosquitoes outdoors is to place two or three drops neat or undiluted on a piece of cloth or ribbon and hang it nearby. The oil can also be added to a small bowl of potpourri, which might be more suitable when entertaining guests.
Do not use any essential oil during pregnancy or on infants or very young children without first consulting a qualified health care practitioner. When applying to skin, take care to avoid sensitive skin around the eyes, nose and mouth. Also, because the inhalation of lavender oil is associated with inducing relaxation, it may potentially increase the effects of anti-anxiety medications in some people.