Hay fever season arrives in late summer and can last into October. The airborne allergens at that time of year are from ragweed and other weed pollens. A more accurate name for rose and hay fever is allergic rhinitis. Symptoms include sneezing, runny nose, congestion, and itchy, watery eyes. Treatment for allergic rhinitis is also discussed at the American Academy of Allergy, Asthma, and Immunology .
Mold spores can be outside at any time of year, except when snow covers the ground.
Indoors, mold is found on houseplants and in damp places such as basements and bathrooms. Dust mites are microscopic creatures that eat skin particles and dander. You can reduce the dust mite population, but they are probably almost impossible to totally remove from your home. There are also hints to help you decrease your exposure to pollen and mold spores as well. During allergy season keep your windows closed and the air-conditioning on.