Ottawa, OH 45875 Frost Dates
When can you plant in Ottawa, OH?
Around 04/19 is the usual last spring frost, about 234 days away. The first fall frost typically arrives around 10/23, about 185 frost-free days later.
Ottawa sits in USDA Zone 6a (-10 to -5°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
About 8 weeks of growing season left in Ottawa before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
The actual range around Ottawa's last frost
04/19 is the middle of 30 years of NOAA records, not a promise. Plant by 04/05 and you're betting against frost in roughly 9 years out of 10. 05/06 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Ottawa compares
Ottawa's growing season runs about 185 days, ranking 23,145 of 40,283 US ZIP codes measured here, longest to shortest. Within OH, it ranks 558 of 1,383.
Learn more
the frost range covers how to read the range around Ottawa's dates instead of trusting one. local microclimates covers what one yard in Ottawa can differ from the 45875 normal.