When to plant in Plymouth, IN
USDA Zone 6aPlymouth, Indiana frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.
Zone 6a means Plymouth sees real winter cold, but a good range of perennials survive; the frost dates above govern when annual vegetables go out.
The average first fall frost in Plymouth is now 7 days later than in the 1981–2010 normals. See how frost dates are shifting nationwide →
Frost probability
PLYMOUTH · 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 Plymouth’s own odds, recorded at PLYMOUTH.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 23 | May 6 | Apr 22 | Sep 27 | Oct 9 | Oct 24 |
| 32°F | May 13 | Apr 25 | Apr 12 | Oct 5 | Oct 21 | Nov 3 |
| 28°F | Apr 30 | Apr 14 | Mar 31 | Oct 19 | Nov 1 | Nov 15 |
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 Plymouth, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 26 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.
Plymouth planting FAQ
When is the last spring frost in Plymouth, IN?
Plan for the last spring frost in Plymouth around April 25 (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 Plymouth, IN?
The first fall frost in Plymouth typically arrives around October 21 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Plymouth in?
Plymouth is in USDA hardiness zone 6a. In zone 6a, winters are moderate — most common vegetables grow well in season.
How long is the growing season in Plymouth?
There are roughly 179 frost-free days in Plymouth (a moderate growing season), running from the average last frost around April 25 to the first fall frost near October 21.
When should I plant tomatoes in Plymouth?
In Plymouth, start tomato seeds indoors around February 28–March 14, then transplant seedlings outdoors around May 2 once the danger of frost has passed.
Never miss a window in Plymouth
An email when it’s time to start seeds, transplant, and sow — timed to Plymouth’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reachFrost dates recorded at PLYMOUTH, 2 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 Plymouth, IN — Frost Dates & Zone 6a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00126989. Retrieved from https://blissgarden.com/indiana/plymouth.