Frost dates for 57779Saint Onge, SD
The average last spring frost in Saint Onge is May 12 and the average first fall frost is October 2, giving a typical growing season of about 143 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 12
- Average first fall frost
- Oct 2
- Growing season
- 143 days
Safer after May 25 (1-in-10 risk)
Possible by Sep 21 (1-in-10 risk)
Last frost typically in 197 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) | May 11 · May 22 · Jun 4 | Sep 9 · Sep 25 · Oct 6 | 124 days | 100% |
| Frost / freeze (32°F) | Apr 29 · May 12 · May 25 | Sep 21 · Oct 2 · Oct 17 | 143 days | 100% |
| Hard freeze (28°F) | Apr 16 · Apr 30 · May 14 | Sep 29 · Oct 12 · Oct 25 | 164 days | 100% |
Planting calendar for Saint Onge
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 | Apr 11 – Jun 17 |
| Tomatoes | Transplant outdoors | May 28 – Jun 12 |
| Peppers | Start seeds indoors | Apr 11 – May 12 |
| Peppers | Transplant outdoors | Jun 11 – Jul 12 |
| Eggplant | Start seeds indoors | Apr 28 – May 27 |
| Eggplant | Transplant outdoors | Jun 11 – Jul 12 |
| Cucumbers | Sow outdoors | Jun 11 – Jun 22 |
| Summer squash | Sow outdoors | May 28 – Jul 12 |
| Winter squash & pumpkins | Sow outdoors | Jun 11 – Jul 12 |
| Snap beans | Sow outdoors | May 28 – Jul 15 |
| Sweet corn | Sow outdoors | May 28 – Jun 12 |
| Watermelon & cantaloupe | Sow outdoors | Jun 11 – Jul 12 |
| Okra | Sow outdoors | Jun 4 – Jun 27 |
| Peas | Sow outdoors (spring) | Apr 11 – May 27 |
| Potatoes | Plant outdoors (spring) | Apr 11 – Jun 11 |
| Onions | Start seeds indoors (spring) | Feb 28 – Mar 27 |
| Onions | Transplant outdoors (spring) | Apr 28 – May 27 |
| Broccoli | Start seeds indoors (spring) | Mar 24 – Apr 27 |
| Broccoli | Transplant outdoors (spring) | Apr 28 – May 27 |
| Broccoli | Start seeds indoors (fall) | Jun 2 – Jun 12 |
| Broccoli | Transplant outdoors (fall) | Jul 2 – Jul 13 |
| Cabbage | Start seeds indoors (spring) | Mar 14 – Apr 11 |
| Cabbage | Transplant outdoors (spring) | Apr 11 – May 12 |
| Cabbage | Start seeds indoors (fall) | May 23 – Jun 22 |
| Cabbage | Transplant outdoors (fall) | Jun 22 – Jul 23 |
| Leaf lettuce | Sow outdoors (spring) | Apr 11 – Jun 27 |
| Leaf lettuce | Sow outdoors (fall) | Jun 22 – Aug 8 |
| Spinach | Sow outdoors (spring) | Apr 4 – May 18 |
| Spinach | Sow outdoors (fall) | Jul 9 – Aug 13 |
| Radishes | Sow outdoors (spring) | Apr 11 – Jun 1 |
| Radishes | Sow outdoors (fall) | Jun 22 – Aug 23 |
| Kale | Sow outdoors (spring) | Apr 28 – May 18 |
| Kale | Sow outdoors (fall) | Jun 15 – Jul 23 |
| Carrots | Sow outdoors (spring) | May 12 – Jun 27 |
| Carrots | Sow outdoors (fall) | May 23 – Jul 8 |
| Garlic | Plant outdoors (fall) | Sep 22 – Oct 23 |
Where these dates come from
ZIP code 57779 is matched to the NOAA station Spearfish, SD, 13 km away, at 3,633 ft elevation (208 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Spearfish, SD (used) | 3,633 ft | May 12 | Oct 2 |
| Belle Fourche, SD | 3,020 ft | May 10 | Sep 30 |
| Deadwood, SD | 4,670 ft | May 24 | Sep 25 |
| Lead, SD | 5,112 ft | May 18 | Sep 29 |
Frost dates near Saint Onge
- Whitewood, SD 57793 · last May 12, first Oct 2
- Spearfish, SD 57783 · last May 12, first Oct 2
- Belle Fourche, SD 57717 · last May 10, first Sep 30
- Deadwood, SD 57732 · last May 24, first Sep 25
- Nisland, SD 57762 · last May 8, first Oct 1
- Fort Meade, SD 57741 · last May 8, first Oct 3
- Beulah, WY 82712 · last May 12, first Oct 2
- Vale, SD 57788 · last May 8, first Oct 1
Frequently asked questions
- When is the last frost in Saint Onge, SD?
- For ZIP code 57779, the average last spring frost (32°F) is May 12, based on NOAA 1991-2020 climate normals for the Spearfish, SD weather station. There is a 1-in-10 chance of a frost after May 25.
- When is the first frost in Saint Onge, SD?
- The average first fall frost (32°F) is October 2. There is a 1-in-10 chance of frost by September 21, so tender plants are at risk from that point on.
- How long is the growing season in 57779?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 143 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.