When to plant in Monroe, OH
USDA Zone 6bEverything below — frost dates, hardiness zone, and what to plant when in Monroe, Ohio — is derived from the closest NOAA station with complete climate normals.
In zone 6b, Monroe gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.
Frost probability
FRANKLIN · 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 Monroe’s own odds, recorded at FRANKLIN.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 19 | May 4 | Apr 20 | Sep 27 | Oct 9 | Oct 21 |
| 32°F | May 11 | Apr 24 | Apr 9 | Oct 7 | Oct 19 | Nov 1 |
| 28°F | Apr 30 | Apr 11 | Mar 26 | Oct 16 | Oct 29 | Nov 11 |
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 Monroe, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 20 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.
Monroe planting FAQ
When is the last spring frost in Monroe, OH?
Plan for the last spring frost in Monroe around April 24 (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 Monroe, OH?
The first fall frost in Monroe typically arrives around October 19 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Monroe in?
Monroe 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 Monroe?
Monroe has about 178 frost-free days — a moderate growing season — between the average last spring frost (April 24) and first fall frost (October 19).
When should I plant tomatoes in Monroe?
For Monroe, sow tomatoes indoors about February 27–March 13 and move the seedlings out around May 1, after the last spring frost.
Never miss a window in Monroe
An email when it’s time to start seeds, transplant, and sow — timed to Monroe’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Middletown · 6 km
- Trenton · 9 km
- Mason · 11 km
- Lebanon · 13 km
- Franklin · 14 km
- Springboro · 17 km
- Hamilton · 18 km
- Sharonville · 19 km
Frost dates recorded at FRANKLIN, 13 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 Monroe, OH — Frost Dates & Zone 6b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00332928. Retrieved from https://blissgarden.com/ohio/monroe.