A: A Dutch botanist incorporated the genes of Chinese citronella grass into an African geranium resulting in a hybrid plant which has the growth habits of a geranium and the scent of citronella. It works best when leaves are crushed and rubbed on the skin. Mosquitos don’t like the scent of citronella and will avoid it. Be sure and “patch test” yourself for any allergy to these leaves by testing a small amount repeatedly on your inner forearm for a day or so; if there’s no irritating skin reaction or redness, then it should be safe to rub on your skin. The mosquito plant has also been called the “citrosa” plant after its chemical constituent. The leaves may contain up to 40% of the repellency of DEET, the active ingredient in DEEP WOODS OFF. Lemon thyme has 62% as much repellant ability as DEEP WOODS OFF! However, the plant as a whole is only about 0.09% citronellal, the chemical in citronella oil. “So,” Arthur Tucker Ph.D., a plant fragrance specialist from Delaware State College, says “the plant will do no good sitting there in a pot, the best chance of it repelling mosquitos if rubbing the crushed leaves on skin after testing a small patch for allergies.” Bottom line – you will need to protect your skin to keep the mosquitoes away. However, a good supply of frogs, toads, lizards and spiders will help keep the pest at bay. Plus, remember to empty any standing water in the bottom of flower pots, old toys or tires, etc. to limit the places for mosquitoes to breed in your yard. They need still, stagnant water for the larvae to reach maturity and remember only the adult female mosquito bites as they need blood to reproduce young.