Frost dates for 57368Plankinton, SD
The average last spring frost in Plankinton is May 3 and the average first fall frost is October 5, giving a typical growing season of about 153 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 3
- Average first fall frost
- Oct 5
- Growing season
- 153 days
Safer after May 17 (1-in-10 risk)
Possible by Sep 21 (1-in-10 risk)
Last frost typically in 181 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 2 · May 12 · May 27 | Sep 15 · Sep 27 · Oct 9 | 136 days | 100% |
| Frost / freeze (32°F) | Apr 20 · May 3 · May 17 | Sep 21 · Oct 5 · Oct 18 | 153 days | 100% |
| Hard freeze (28°F) | Apr 11 · Apr 25 · May 7 | Sep 29 · Oct 14 · Oct 27 | 170 days | 100% |
Planting calendar for Plankinton
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 2 – Jun 8 |
| Tomatoes | Transplant outdoors | May 19 – Jun 15 |
| Peppers | Start seeds indoors | Apr 2 – May 3 |
| Peppers | Transplant outdoors | Jun 2 – Jul 3 |
| Eggplant | Start seeds indoors | Apr 19 – May 18 |
| Eggplant | Transplant outdoors | Jun 2 – Jul 3 |
| Cucumbers | Sow outdoors | Jun 2 – Jun 25 |
| Summer squash | Sow outdoors | May 19 – Jul 3 |
| Winter squash & pumpkins | Sow outdoors | Jun 2 – Jul 3 |
| Snap beans | Sow outdoors | May 19 – Jul 18 |
| Sweet corn | Sow outdoors | May 19 – Jun 15 |
| Watermelon & cantaloupe | Sow outdoors | Jun 2 – Jul 3 |
| Okra | Sow outdoors | May 26 – Jun 18 |
| Peas | Sow outdoors (spring) | Apr 2 – May 18 |
| Potatoes | Plant outdoors (spring) | Apr 2 – Jun 2 |
| Onions | Start seeds indoors (spring) | Feb 19 – Mar 18 |
| Onions | Transplant outdoors (spring) | Apr 19 – May 18 |
| Broccoli | Start seeds indoors (spring) | Mar 15 – Apr 18 |
| Broccoli | Transplant outdoors (spring) | Apr 19 – May 18 |
| Broccoli | Start seeds indoors (fall) | Jun 5 – Jun 15 |
| Broccoli | Transplant outdoors (fall) | Jul 5 – Jul 16 |
| Cabbage | Start seeds indoors (spring) | Mar 5 – Apr 2 |
| Cabbage | Transplant outdoors (spring) | Apr 2 – May 3 |
| Cabbage | Start seeds indoors (fall) | May 26 – Jun 25 |
| Cabbage | Transplant outdoors (fall) | Jun 25 – Jul 26 |
| Leaf lettuce | Sow outdoors (spring) | Apr 2 – Jun 18 |
| Leaf lettuce | Sow outdoors (fall) | Jun 25 – Aug 11 |
| Spinach | Sow outdoors (spring) | Mar 26 – May 9 |
| Spinach | Sow outdoors (fall) | Jul 12 – Aug 16 |
| Radishes | Sow outdoors (spring) | Apr 2 – May 23 |
| Radishes | Sow outdoors (fall) | Jun 25 – Aug 26 |
| Kale | Sow outdoors (spring) | Apr 19 – May 9 |
| Kale | Sow outdoors (fall) | Jun 18 – Jul 26 |
| Carrots | Sow outdoors (spring) | May 3 – Jun 18 |
| Carrots | Sow outdoors (fall) | May 26 – Jul 11 |
| Garlic | Plant outdoors (fall) | Sep 25 – Oct 26 |
Where these dates come from
ZIP code 57368 is matched to the NOAA station White Lake, SD, 17.2 km away, at 1,629 ft elevation (133 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| White Lake, SD (used) | 1,629 ft | May 3 | Oct 5 |
| Mitchell, SD | 1,287 ft | Apr 27 | Oct 11 |
| Mitchell Muni Ap, SD | 1,303 ft | Apr 30 | Oct 5 |
| Mitchell 2 N, SD | 1,250 ft | May 2 | Oct 6 |
Frost dates near Plankinton
- Mount Vernon, SD 57363 · last Apr 30, first Oct 5
- Stickney, SD 57375 · last May 3, first Oct 5
- White Lake, SD 57383 · last May 3, first Oct 5
- Letcher, SD 57359 · last Apr 30, first Oct 5
- Harrison, SD 57344 · last May 3, first Oct 6
- Mitchell, SD 57301 · last Apr 30, first Oct 5
- New Holland, SD 57364 · last May 3, first Oct 6
- Corsica, SD 57328 · last May 3, first Oct 6
Frequently asked questions
- When is the last frost in Plankinton, SD?
- For ZIP code 57368, the average last spring frost (32°F) is May 3, based on NOAA 1991-2020 climate normals for the White Lake, SD weather station. There is a 1-in-10 chance of a frost after May 17.
- When is the first frost in Plankinton, SD?
- The average first fall frost (32°F) is October 5. 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 57368?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 153 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.