Plant a Nose-Friendly Garden
The best way to deal with yard work is to sit back with a cold drink and have someone else do it. Failing that...
Wear a microfiber mask whenever you dig around in the dirt, rake leaves, or mow the lawn. All these activities are guaranteed to stir up pollen and mold.
Take an antihistamine, or use cromolyn sodium 30 minutes before you start.
Leave your outer work clothes outside after you've finished, and wash them before wearing them again.
Shower immediately after you come inside.
During the spring grass season, cut the grass short, before it can sprout pollen-producing flowers.
Get rid of the compost heap (a prime source of mold), or at the very least, keep it as far from the house as possible.
Consider replacing plants that produce lots of offending pollen with more benign varieties. Rules of green thumb: Choose showy, flowering trees and shrubs such as apple and cherry trees and azaleas; they produce waxy pollen that's too heavy to ride the breeze. On the lawn, opt for nonpollinating ground cover such as myrtle and ivy rather than grass.