Ortley, SD frost dates
How Ortley compares
- In 8 years out of 10, the last spring frost in Ortley falls between May 1 and May 28, a 27-day window. The first fall frost falls between September 13 and October 10.
- The median last frost is 8 days later than the South Dakota median of May 6.
- Its 137-day growing season is longer than 8% of the 363 South Dakota places with a regular frost season (state median 149 days).
- The last frost is 6 days later than the zone 4b median of May 8. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 4b chart.
- The weather station records an average of 180 nights a year at or below 32°F.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | May 1 |
| 50% (median) | May 14 |
| 10% (safe for tender plants) | May 28 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 13 |
| 50% (median) | September 28 |
| 90% (late) | October 10 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for Ortley, SD
Ortley, SD frost dates — last frost May 14, first frost Sep 28, zone 4b. whenisthelastfrost.com
When to plant vegetables in Ortley, SD
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 19 – Mar 5 | Apr 16 – Apr 30 | — | — |
| Peppers | Mar 5 – Mar 19 | May 28 – Jun 11 | — | — |
| Eggplant | Mar 5 – Mar 19 | May 28 – Jun 11 | — | — |
| Tomatoes | Mar 19 – Apr 2 | May 21 – Jun 4 | — | — |
| Lettuce | Mar 19 – Apr 2 | Apr 23 – May 7 | Apr 16 – May 21 | Aug 3 – Aug 31 |
| Kale | Mar 19 – Apr 2 | Apr 16 – Apr 30 | Apr 16 – Apr 30 | Jul 20 – Aug 10 |
| Broccoli | Mar 19 – Apr 2 | Apr 30 – May 14 | — | Jun 22 – Jul 13 |
| Cabbage | Mar 19 – Apr 2 | Apr 23 – May 7 | — | Jun 22 – Jul 13 |
| Cauliflower | Mar 19 – Apr 2 | Apr 30 – May 14 | — | Jun 22 – Jul 13 |
| Okra | Apr 2 – Apr 16 | Jun 4 – Jun 18 | Jun 4 – Jun 18 | — |
| Basil | Apr 2 – Apr 16 | May 21 – Jun 4 | — | — |
| Peas | — | — | Apr 2 – Apr 23 | Jul 6 – Jul 27 |
| Spinach | — | — | Apr 2 – Apr 23 | Aug 3 – Aug 24 |
| Radishes | — | — | Apr 9 – May 21 | Aug 17 – Sep 7 |
| Cucumbers | Apr 16 – Apr 23 | May 28 – Jun 4 | May 21 – Jun 4 | Jul 13 – Jul 27 |
| Zucchini & Summer Squash | Apr 16 – Apr 23 | — | May 21 – Jun 4 | Jul 20 – Aug 3 |
| Winter Squash & Pumpkins | Apr 16 – Apr 23 | — | May 21 – Jun 4 | — |
| Melons & Watermelon | Apr 16 – Apr 23 | May 28 – Jun 11 | — | — |
| Carrots | — | — | Apr 23 – May 21 | Jul 6 – Jul 20 |
| Beets | — | — | Apr 23 – May 21 | Jul 20 – Aug 3 |
| Potatoes | — | — | Apr 23 – May 14 | — |
| Swiss Chard | — | — | Apr 30 – May 28 | Jul 20 – Aug 3 |
| Cilantro | — | — | Apr 30 – May 21 | Aug 3 – Aug 24 |
| Green Beans | — | — | May 21 – Jun 11 | Jul 13 – Jul 27 |
| Sweet Corn | — | — | May 21 – Jun 4 | — |
| Sweet Potatoes | — | May 28 – Jun 18 | — | — |
| Garlic | — | — | — | Sep 14 – Oct 19 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the Summit 1 W, SD weather station, 11 km away (elevation 1,955 ft (596 m)).
Frost dates near Ortley
- Waubay May 1 · Oct 12
- Summit May 14 · Sep 28
- Marvin May 14 · Sep 28
- South Shore May 7 · Sep 28
- Florence May 7 · Sep 28
- Webster May 4 · Oct 6
- Wallace May 7 · Sep 28
- Grenville May 1 · Oct 12
- Twin Brooks May 2 · Oct 4
- Wilmot May 5 · Oct 1
Frequently asked questions
When is the last frost in Ortley, SD?
The median last spring frost in Ortley, SD is May 14. There is still about a 10% chance of frost after May 28, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Ortley, SD?
The median first fall frost is September 28, with about a 10% chance of frost before September 13.
How long is the growing season in Ortley, SD?
About 137 days between the median last spring frost and first fall frost.
What planting zone is Ortley, SD?
Ortley, SD is in USDA hardiness zone 4b.