When to plant in Cottage Grove, MN
USDA Zone 5aHere are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for Cottage Grove, Minnesota — all computed from Cottage Grove's nearest NOAA weather station.
In zone 5a, Cottage Grove gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.
Frost probability
HASTINGS DAM 2 · 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 Cottage Grove’s own odds, recorded at HASTINGS DAM 2.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 19 | May 4 | Apr 19 | Sep 26 | Oct 8 | Oct 22 |
| 32°F | May 7 | Apr 23 | Apr 8 | Oct 5 | Oct 19 | Nov 1 |
| 28°F | Apr 30 | Apr 11 | Apr 1 | Oct 14 | Oct 30 | Nov 12 |
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 Cottage Grove, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 17 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.
Cottage Grove planting FAQ
When is the last spring frost in Cottage Grove, MN?
Cottage Grove's average last spring frost falls near April 23 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.
When is the first fall frost in Cottage Grove, MN?
The first fall frost in Cottage Grove typically arrives around October 19 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Cottage Grove in?
Cottage Grove is in USDA hardiness zone 5a. In zone 5a, winters are cold — pick cold-hardy varieties and protect tender crops.
How long is the growing season in Cottage Grove?
Cottage Grove has about 179 frost-free days — a moderate growing season — between the average last spring frost (April 23) and first fall frost (October 19).
When should I plant tomatoes in Cottage Grove?
For Cottage Grove, sow tomatoes indoors about February 26–March 12 and move the seedlings out around April 30, after the last spring frost.
Never miss a window in Cottage Grove
An email when it’s time to start seeds, transplant, and sow — timed to Cottage Grove’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Hastings · 10 km
- Woodbury · 10 km
- Inver Grove Heights · 12 km
- South St. Paul · 13 km
- Rosemount · 14 km
- West St. Paul · 17 km
- Mendota Heights · 19 km
- Lake Elmo · 19 km
Frost dates recorded at HASTINGS DAM 2, 7 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 Cottage Grove, MN — Frost Dates & Zone 5a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00213567. Retrieved from https://blissgarden.com/minnesota/cottage-grove.