When to plant in Hamilton, OH
USDA Zone 6bHere are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for Hamilton, Ohio — all computed from Hamilton's nearest NOAA weather station.
Zone 6b means Hamilton sees real winter cold, but a good range of perennials survive; the frost dates above govern when annual vegetables go out.
Frost probability
HAMILTON BUTLER CO RGNL AP · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Hamilton’s own odds, recorded at HAMILTON BUTLER CO RGNL AP.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 19 | May 2 | Apr 18 | Sep 25 | Oct 7 | Oct 20 |
| 32°F | May 10 | Apr 22 | Apr 6 | Oct 5 | Oct 18 | Oct 29 |
| 28°F | Apr 28 | Apr 8 | Mar 26 | Oct 15 | Oct 27 | Nov 8 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Hamilton, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 27 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
Hamilton planting FAQ
When is the last spring frost in Hamilton, OH?
Plan for the last spring frost in Hamilton around April 22 (the date it has a 50% chance of a 32°F freeze). Anything frost-sensitive should go out after it.
When is the first fall frost in Hamilton, OH?
Expect Hamilton's first fall frost near October 18 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.
What hardiness zone is Hamilton in?
Hamilton is in USDA hardiness zone 6b. In zone 6b, winters are moderate — most common vegetables grow well in season.
How long is the growing season in Hamilton?
There are roughly 179 frost-free days in Hamilton (a moderate growing season), running from the average last frost around April 22 to the first fall frost near October 18.
When should I plant tomatoes in Hamilton?
In Hamilton, start tomato seeds indoors around February 25–March 11, then transplant seedlings outdoors around April 29 once the danger of frost has passed.
Never miss a window in Hamilton
An email when it’s time to start seeds, transplant, and sow — timed to Hamilton’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Fairfield · 7 km
- Forest Park · 12 km
- Trenton · 13 km
- Springdale · 14 km
- Northbrook · 16 km
- Monroe · 18 km
- Sharonville · 19 km
- Oxford · 20 km
Frost dates recorded at HAMILTON BUTLER CO RGNL AP, 5 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Hamilton, OH — Frost Dates & Zone 6b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00053855. Retrieved from https://blissgarden.com/ohio/hamilton.