Ohio's mix of urban parks and agricultural land creates prolonged allergy seasons. Tree pollen peaks in April-May, grass dominates June-July, and ragweed is significant from August through October.
Peak pollen season in Ohio: April–September. Primary allergens: OakGrassRagweed
Tree pollen is the first major allergen each year in Ohio, typically starting in early spring with cedar and alder, followed by oak and birch through May.
Grass pollen takes over in late spring through early summer, peaking from May to July depending on location within the state.
Ragweed dominates fall allergies in Ohio, typically from August through October. It's the most widespread fall allergen in the US.
The pollen count in Ohio varies by city and season. Peak pollen season runs April–September. Select a city above for live data.
Pollen levels vary across Ohio. Cities in warmer, more humid areas typically see higher counts. Check individual city pages for current levels.
Pollen season in Ohio peaks in April–September. Tree pollen starts in late winter, followed by grass in summer and ragweed in fall.