Don’t Count On Catnip Against West Nile Virus

Q. I read the article about using catnip as a mosquito repellent. Will merely planting catnip around the house ward off mosquitoes? Or is it necessary to crush the leaves, releasing the plants’ oils?
Given the situation with West Nile virus, it would be wonderful if using catnip as a foliage planting could create a safer zone around our homes.
A. The ingredient in catnip that appears to have mosquito repellent properties is nepetalactone. To activate the compound you have to crush the leaves and release the volatile oil. Just planting catnip around your house is unlikely to afford any protection from mosquitoes.