When to plant in Mankato, MN
USDA Zone 5aEverything below — frost dates, hardiness zone, and what to plant when in Mankato, Minnesota — is derived from the closest NOAA station with complete climate normals.
In zone 5a, Mankato gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.
The average first fall frost in Mankato is now 6 days later than in the 1981–2010 normals. See how frost dates are shifting nationwide →
Frost probability
MANKATO · 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 Mankato’s own odds, recorded at MANKATO.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 23 | May 8 | Apr 26 | Sep 17 | Sep 30 | Oct 12 |
| 32°F | May 12 | Apr 30 | Apr 16 | Sep 25 | Oct 9 | Oct 22 |
| 28°F | May 2 | Apr 19 | Apr 6 | Oct 4 | Oct 20 | Nov 1 |
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 Mankato, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 35 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.
Mankato planting FAQ
When is the last spring frost in Mankato, MN?
Mankato's average last spring frost falls near April 30 — 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 Mankato, MN?
The first fall frost in Mankato typically arrives around October 9 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Mankato in?
Mankato 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 Mankato?
Mankato has about 162 frost-free days — a moderate growing season — between the average last spring frost (April 30) and first fall frost (October 9).
When should I plant tomatoes in Mankato?
For Mankato, sow tomatoes indoors about March 5–March 19 and move the seedlings out around May 7, after the last spring frost.
Never miss a window in Mankato
An email when it’s time to start seeds, transplant, and sow — timed to Mankato’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- North Mankato · 5 km
- St. Peter · 18 km
- New Ulm · 42 km
- Faribault · 57 km
- Owatonna · 60 km
- Fairmont · 70 km
- Northfield · 71 km
- Prior Lake · 75 km
Frost dates recorded at MANKATO, 4 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 Mankato, MN — Frost Dates & Zone 5a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00215073. Retrieved from https://blissgarden.com/minnesota/mankato.