Frost dates for 57702 — Rapid City, SD
Last spring frostMay 20median date
First fall frostSep 25median date
Growing season128 daysfrost-free
Hardiness zone5aZone 5a
How Rapid City compares
- In 8 years out of 10, the last spring frost in Rapid City falls between May 9 and June 3, a 25-day window. The first fall frost falls between September 11 and October 7.
- The median last frost is 14 days later than the South Dakota median of May 6.
- Its 128-day growing season is among the shortest of the 363 South Dakota places with a regular frost season.
- The last frost is 17 days later than the zone 5a median of May 3. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 5a chart.
- The weather station records an average of 190 nights a year at or below 32°F.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | May 9 |
| 50% (median) | May 20 |
| 10% (safe for tender plants) | June 3 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 11 |
| 50% (median) | September 25 |
| 90% (late) | October 7 |
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 Rapid City, SD
Frost dates for 57702 — Rapid City, SD — last frost May 20, first frost Sep 25, zone 5a. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Feb 25 to Mar 11Transplant outside: Apr 22 to May 6
Start indoors: Mar 11 to Mar 25Transplant outside: Jun 3 to Jun 17
Start indoors: Mar 11 to Mar 25Transplant outside: Jun 3 to Jun 17
Start indoors: Mar 25 to Apr 8Transplant outside: May 27 to Jun 10
Start indoors: Mar 25 to Apr 8Transplant outside: Apr 29 to May 13Sow outdoors: Apr 22 to May 27Plant for fall: Jul 31 to Aug 28
Start indoors: Mar 25 to Apr 8Transplant outside: Apr 22 to May 6Sow outdoors: Apr 22 to May 6Plant for fall: Jul 17 to Aug 7
Start indoors: Mar 25 to Apr 8Transplant outside: May 6 to May 20Plant for fall: Jun 19 to Jul 10
Start indoors: Mar 25 to Apr 8Transplant outside: Apr 29 to May 13Plant for fall: Jun 19 to Jul 10
Start indoors: Mar 25 to Apr 8Transplant outside: May 6 to May 20Plant for fall: Jun 19 to Jul 10
Start indoors: Apr 8 to Apr 22Transplant outside: Jun 10 to Jun 24Sow outdoors: Jun 10 to Jun 24
Start indoors: Apr 8 to Apr 22Transplant outside: May 27 to Jun 10
Sow outdoors: Apr 8 to Apr 29Plant for fall: Jul 3 to Jul 24
Sow outdoors: Apr 8 to Apr 29Plant for fall: Jul 31 to Aug 21
Sow outdoors: Apr 15 to May 27Plant for fall: Aug 14 to Sep 4
Start indoors: Apr 22 to Apr 29Transplant outside: Jun 3 to Jun 10Sow outdoors: May 27 to Jun 10Plant for fall: Jul 10 to Jul 24
Start indoors: Apr 22 to Apr 29Sow outdoors: May 27 to Jun 10Plant for fall: Jul 17 to Jul 31
Start indoors: Apr 22 to Apr 29Sow outdoors: May 27 to Jun 10
Start indoors: Apr 22 to Apr 29Transplant outside: Jun 3 to Jun 17
Sow outdoors: Apr 29 to May 27Plant for fall: Jul 3 to Jul 17
Sow outdoors: Apr 29 to May 27Plant for fall: Jul 17 to Jul 31
Sow outdoors: Apr 29 to May 20
Sow outdoors: May 6 to Jun 3Plant for fall: Jul 17 to Jul 31
Sow outdoors: May 6 to May 27Plant for fall: Jul 31 to Aug 21
Sow outdoors: May 27 to Jun 17Plant for fall: Jul 10 to Jul 24
Sow outdoors: May 27 to Jun 10
Transplant outside: Jun 3 to Jun 24
Plant for fall: Sep 11 to Oct 16
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Rapid City, SD
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 25 – Mar 11 | Apr 22 – May 6 | — | — |
| Peppers | Mar 11 – Mar 25 | Jun 3 – Jun 17 | — | — |
| Eggplant | Mar 11 – Mar 25 | Jun 3 – Jun 17 | — | — |
| Tomatoes | Mar 25 – Apr 8 | May 27 – Jun 10 | — | — |
| Lettuce | Mar 25 – Apr 8 | Apr 29 – May 13 | Apr 22 – May 27 | Jul 31 – Aug 28 |
| Kale | Mar 25 – Apr 8 | Apr 22 – May 6 | Apr 22 – May 6 | Jul 17 – Aug 7 |
| Broccoli | Mar 25 – Apr 8 | May 6 – May 20 | — | Jun 19 – Jul 10 |
| Cabbage | Mar 25 – Apr 8 | Apr 29 – May 13 | — | Jun 19 – Jul 10 |
| Cauliflower | Mar 25 – Apr 8 | May 6 – May 20 | — | Jun 19 – Jul 10 |
| Okra | Apr 8 – Apr 22 | Jun 10 – Jun 24 | Jun 10 – Jun 24 | — |
| Basil | Apr 8 – Apr 22 | May 27 – Jun 10 | — | — |
| Peas | — | — | Apr 8 – Apr 29 | Jul 3 – Jul 24 |
| Spinach | — | — | Apr 8 – Apr 29 | Jul 31 – Aug 21 |
| Radishes | — | — | Apr 15 – May 27 | Aug 14 – Sep 4 |
| Cucumbers | Apr 22 – Apr 29 | Jun 3 – Jun 10 | May 27 – Jun 10 | Jul 10 – Jul 24 |
| Zucchini & Summer Squash | Apr 22 – Apr 29 | — | May 27 – Jun 10 | Jul 17 – Jul 31 |
| Winter Squash & Pumpkins | Apr 22 – Apr 29 | — | May 27 – Jun 10 | — |
| Melons & Watermelon | Apr 22 – Apr 29 | Jun 3 – Jun 17 | — | — |
| Carrots | — | — | Apr 29 – May 27 | Jul 3 – Jul 17 |
| Beets | — | — | Apr 29 – May 27 | Jul 17 – Jul 31 |
| Potatoes | — | — | Apr 29 – May 20 | — |
| Swiss Chard | — | — | May 6 – Jun 3 | Jul 17 – Jul 31 |
| Cilantro | — | — | May 6 – May 27 | Jul 31 – Aug 21 |
| Green Beans | — | — | May 27 – Jun 17 | Jul 10 – Jul 24 |
| Sweet Corn | — | — | May 27 – Jun 10 | — |
| Sweet Potatoes | — | Jun 3 – Jun 24 | — | — |
| Garlic | — | — | — | Sep 11 – Oct 16 |
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 Johnson Siding, SD weather station, 11 km away (elevation 4,183 ft (1,275 m)).
ZIP codes in Rapid City: 57701 57702 57703 57709
Frost dates near Rapid City
- Keystone May 15 · Oct 1
- Black Hawk May 10 · Oct 5
- Hill City Jun 1 · Sep 10
- Hermosa May 15 · Oct 1
- Piedmont May 10 · Oct 5
- Box Elder May 12 · Oct 1
- Nemo May 20 · Sep 25
- Ellsworth Afb May 12 · Oct 1
Frequently asked questions
When is the last frost in Rapid City, SD?
The median last spring frost in Rapid City, SD is May 20. There is still about a 10% chance of frost after June 3, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Rapid City, SD?
The median first fall frost is September 25, with about a 10% chance of frost before September 11.
How long is the growing season in Rapid City, SD?
About 128 days between the median last spring frost and first fall frost.
What planting zone is Rapid City, SD?
Rapid City, SD is in USDA hardiness zone 5a.