Frost dates for 55109Saint Paul, MN
The average last spring frost in Saint Paul is April 23 and the average first fall frost is October 20, giving a typical growing season of about 177 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 23
- Average first fall frost
- Oct 20
- Growing season
- 177 days
Safer after May 7 (1-in-10 risk)
Possible by Oct 3 (1-in-10 risk)
Last frost typically in 179 days
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | Apr 19 · May 2 · May 16 | Sep 24 · Oct 7 · Oct 20 | 157 days | 100% |
| Frost / freeze (32°F) | Apr 9 · Apr 23 · May 7 | Oct 3 · Oct 20 · Nov 2 | 177 days | 100% |
| Hard freeze (28°F) | Apr 2 · Apr 14 · Apr 27 | Oct 15 · Oct 31 · Nov 12 | 197 days | 100% |
Planting calendar for Saint Paul
Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.
| Crop | Task | Window |
|---|---|---|
| Tomatoes | Start seeds indoors | Mar 23 – May 29 |
| Tomatoes | Transplant outdoors | May 9 – Jun 30 |
| Peppers | Start seeds indoors | Mar 23 – Apr 23 |
| Peppers | Transplant outdoors | May 23 – Jun 23 |
| Eggplant | Start seeds indoors | Apr 9 – May 8 |
| Eggplant | Transplant outdoors | May 23 – Jun 23 |
| Cucumbers | Sow outdoors | May 23 – Jul 10 |
| Summer squash | Sow outdoors | May 9 – Jun 23 |
| Winter squash & pumpkins | Sow outdoors | May 23 – Jun 23 |
| Snap beans | Sow outdoors | May 9 – Aug 2 |
| Sweet corn | Sow outdoors | May 9 – Jun 30 |
| Watermelon & cantaloupe | Sow outdoors | May 23 – Jun 23 |
| Okra | Sow outdoors | May 16 – Jun 8 |
| Peas | Sow outdoors (spring) | Mar 23 – May 8 |
| Potatoes | Plant outdoors (spring) | Mar 23 – May 23 |
| Onions | Start seeds indoors (spring) | Feb 9 – Mar 8 |
| Onions | Transplant outdoors (spring) | Apr 9 – May 8 |
| Broccoli | Start seeds indoors (spring) | Mar 5 – Apr 8 |
| Broccoli | Transplant outdoors (spring) | Apr 9 – May 8 |
| Broccoli | Start seeds indoors (fall) | Jun 20 – Jun 30 |
| Broccoli | Transplant outdoors (fall) | Jul 20 – Jul 31 |
| Cabbage | Start seeds indoors (spring) | Feb 23 – Mar 23 |
| Cabbage | Transplant outdoors (spring) | Mar 23 – Apr 23 |
| Cabbage | Start seeds indoors (fall) | Jun 10 – Jul 10 |
| Cabbage | Transplant outdoors (fall) | Jul 10 – Aug 10 |
| Leaf lettuce | Sow outdoors (spring) | Mar 23 – Jun 8 |
| Leaf lettuce | Sow outdoors (fall) | Jul 10 – Aug 26 |
| Spinach | Sow outdoors (spring) | Mar 16 – Apr 29 |
| Spinach | Sow outdoors (fall) | Jul 27 – Aug 31 |
| Radishes | Sow outdoors (spring) | Mar 23 – May 13 |
| Radishes | Sow outdoors (fall) | Jul 10 – Sep 10 |
| Kale | Sow outdoors (spring) | Apr 9 – Apr 29 |
| Kale | Sow outdoors (fall) | Jul 3 – Aug 10 |
| Carrots | Sow outdoors (spring) | Apr 23 – Jun 8 |
| Carrots | Sow outdoors (fall) | Jun 10 – Jul 26 |
| Garlic | Plant outdoors (fall) | Oct 10 – Nov 10 |
Where these dates come from
ZIP code 55109 is matched to the NOAA station Vadnais Lake, MN, 6.5 km away, at 890 ft elevation (35 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Vadnais Lake, MN (used) | 890 ft | Apr 23 | Oct 20 |
| St Paul, MN | 900 ft | Apr 26 | Oct 12 |
| St Paul Downtown Ap, MN | 700 ft | Apr 24 | Oct 16 |
| U Of Mn St Paul, MN | 970 ft | Apr 28 | Oct 8 |
Frost dates near Saint Paul
- Stillwater, MN 55083 · last Apr 23, first Oct 20
- Saint Paul, MN 55106 · last Apr 23, first Oct 20
- Willernie, MN 55090 · last Apr 23, first Oct 20
- Lake Elmo, MN 55042 · last Apr 23, first Oct 20
- South Saint Paul, MN 55075 · last Apr 24, first Oct 16
- Minneapolis, MN 55414 · last Apr 23, first Oct 16
- Newport, MN 55055 · last Apr 24, first Oct 16
- Mendota, MN 55150 · last Apr 23, first Oct 18
Frequently asked questions
- When is the last frost in Saint Paul, MN?
- For ZIP code 55109, the average last spring frost (32°F) is April 23, based on NOAA 1991-2020 climate normals for the Vadnais Lake, MN weather station. There is a 1-in-10 chance of a frost after May 7.
- When is the first frost in Saint Paul, MN?
- The average first fall frost (32°F) is October 20. There is a 1-in-10 chance of frost by October 3, so tender plants are at risk from that point on.
- How long is the growing season in 55109?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 177 days long.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.