I get ragweed September through October.
Use a neti pot, immediate shower after each ride, otherwise stay indoors, and always keep the contacts clean.
I watch the pollen forecasts at like pollen.com and take loratadine the night before.
I'm convinced the meds have an effect on my training so I try to avoid them. Plus they make you congested unless you get the one with decongestant but then you've got more side effects and drowsiness.
First season with the neti pot; so far so good.