A member of the geranium family, Citronella is a great patio plant, especially in containers. Go easy on the fertilizer, because too much nitrogen can reduce the fragrance of the leaves. Although the oil from crushed leaves may have some ability to discourage mosquitoes, the plants alone are grown more for their citrus scent than as a mosquito repellent. Place citronella where you can brush against the leaves as you walk by, or in a pot where you can rub the leaves to enjoy their fragrance. Plants are vigorous growers and drought tolerant. Be sure to move indoors before frost.