Hayfever sufferers may do better at the shore, since the wind often blows in from the sea. Or one can head for the mountains, where pollen counts tend to be lower. For example, Hawaii has grass pollination year round. Southern states typically have the longest pollination period. Grasses pollinate 10-11 months of the year.
Trees pollinate early, but have limited seasons.
For example, Elm trees pollinate for 2-3 weeks. The exception to this is a milder winter, which can cause pollination to peak higher and last longer. Know when the plants that trigger your allergies are in bloom and avoid visiting at that time of year. Time your trip to coincide with low levels of pollen. If traveling by car, close the windows and use the air conditioner.