Answer: Though there are plants, like lemon balm, that contain citronella oil, they do not, unfortunately, provide a repellent effect unless you bruise the leaves to release the oil. (You may have seen ads claiming that a particular plant does the trick, but it isn't the case.) During the heat of the day, mosquitos (just like people) enjoy shade, cool temperatures, and high humidity provided by overhanging trees and other vegetation, so if you have a high concentration of mosquitos in your yard, that may be the reason.
Mosquito control is almost impossible to acheive on a yard-by-yard basis. You can try citronella candles, torches, and insence, or wear repllent, and see if that helps. Generally, mosquito populations need to be managed on a large scale to have any noticeable effect. Sorry I can't be more helpful!
Q&A Library Searching Tips