Smithwick, SD frost dates
Last spring frostMay 15median date
First fall frostSep 27median date
Growing season135 daysfrost-free
Hardiness zone5aZone 5a
How Smithwick compares
- In 8 years out of 10, the last spring frost in Smithwick falls between May 5 and May 28, a 23-day window. The first fall frost falls between September 11 and October 8.
- The median last frost is 9 days later than the South Dakota median of May 6.
- Its 135-day growing season is longer than 6% of the 363 South Dakota places with a regular frost season (state median 149 days).
- The last frost is 12 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 186 nights a year at or below 32°F.
- Compared with Rapid City, SD, 85 km away, the last frost here is 12 days later than there and the growing season is 23 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | May 5 |
| 50% (median) | May 15 |
| 10% (safe for tender plants) | May 28 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 11 |
| 50% (median) | September 27 |
| 90% (late) | October 8 |
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 Smithwick, SD
Smithwick, SD frost dates — last frost May 15, first frost Sep 27, zone 5a. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Feb 20 to Mar 6Transplant outside: Apr 17 to May 1
Start indoors: Mar 6 to Mar 20Transplant outside: May 29 to Jun 12
Start indoors: Mar 6 to Mar 20Transplant outside: May 29 to Jun 12
Start indoors: Mar 20 to Apr 3Transplant outside: May 22 to Jun 5
Start indoors: Mar 20 to Apr 3Transplant outside: Apr 24 to May 8Sow outdoors: Apr 17 to May 22Plant for fall: Aug 2 to Aug 30
Start indoors: Mar 20 to Apr 3Transplant outside: Apr 17 to May 1Sow outdoors: Apr 17 to May 1Plant for fall: Jul 19 to Aug 9
Start indoors: Mar 20 to Apr 3Transplant outside: May 1 to May 15Plant for fall: Jun 21 to Jul 12
Start indoors: Mar 20 to Apr 3Transplant outside: Apr 24 to May 8Plant for fall: Jun 21 to Jul 12
Start indoors: Mar 20 to Apr 3Transplant outside: May 1 to May 15Plant for fall: Jun 21 to Jul 12
Start indoors: Apr 3 to Apr 17Transplant outside: Jun 5 to Jun 19Sow outdoors: Jun 5 to Jun 19
Start indoors: Apr 3 to Apr 17Transplant outside: May 22 to Jun 5
Sow outdoors: Apr 3 to Apr 24Plant for fall: Jul 5 to Jul 26
Sow outdoors: Apr 3 to Apr 24Plant for fall: Aug 2 to Aug 23
Sow outdoors: Apr 10 to May 22Plant for fall: Aug 16 to Sep 6
Start indoors: Apr 17 to Apr 24Transplant outside: May 29 to Jun 5Sow outdoors: May 22 to Jun 5Plant for fall: Jul 12 to Jul 26
Start indoors: Apr 17 to Apr 24Sow outdoors: May 22 to Jun 5Plant for fall: Jul 19 to Aug 2
Start indoors: Apr 17 to Apr 24Sow outdoors: May 22 to Jun 5
Start indoors: Apr 17 to Apr 24Transplant outside: May 29 to Jun 12
Sow outdoors: Apr 24 to May 22Plant for fall: Jul 5 to Jul 19
Sow outdoors: Apr 24 to May 22Plant for fall: Jul 19 to Aug 2
Sow outdoors: Apr 24 to May 15
Sow outdoors: May 1 to May 29Plant for fall: Jul 19 to Aug 2
Sow outdoors: May 1 to May 22Plant for fall: Aug 2 to Aug 23
Sow outdoors: May 22 to Jun 12Plant for fall: Jul 12 to Jul 26
Sow outdoors: May 22 to Jun 5
Transplant outside: May 29 to Jun 19
Plant for fall: Sep 13 to Oct 18
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Smithwick, SD
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 20 – Mar 6 | Apr 17 – May 1 | — | — |
| Peppers | Mar 6 – Mar 20 | May 29 – Jun 12 | — | — |
| Eggplant | Mar 6 – Mar 20 | May 29 – Jun 12 | — | — |
| Tomatoes | Mar 20 – Apr 3 | May 22 – Jun 5 | — | — |
| Lettuce | Mar 20 – Apr 3 | Apr 24 – May 8 | Apr 17 – May 22 | Aug 2 – Aug 30 |
| Kale | Mar 20 – Apr 3 | Apr 17 – May 1 | Apr 17 – May 1 | Jul 19 – Aug 9 |
| Broccoli | Mar 20 – Apr 3 | May 1 – May 15 | — | Jun 21 – Jul 12 |
| Cabbage | Mar 20 – Apr 3 | Apr 24 – May 8 | — | Jun 21 – Jul 12 |
| Cauliflower | Mar 20 – Apr 3 | May 1 – May 15 | — | Jun 21 – Jul 12 |
| Okra | Apr 3 – Apr 17 | Jun 5 – Jun 19 | Jun 5 – Jun 19 | — |
| Basil | Apr 3 – Apr 17 | May 22 – Jun 5 | — | — |
| Peas | — | — | Apr 3 – Apr 24 | Jul 5 – Jul 26 |
| Spinach | — | — | Apr 3 – Apr 24 | Aug 2 – Aug 23 |
| Radishes | — | — | Apr 10 – May 22 | Aug 16 – Sep 6 |
| Cucumbers | Apr 17 – Apr 24 | May 29 – Jun 5 | May 22 – Jun 5 | Jul 12 – Jul 26 |
| Zucchini & Summer Squash | Apr 17 – Apr 24 | — | May 22 – Jun 5 | Jul 19 – Aug 2 |
| Winter Squash & Pumpkins | Apr 17 – Apr 24 | — | May 22 – Jun 5 | — |
| Melons & Watermelon | Apr 17 – Apr 24 | May 29 – Jun 12 | — | — |
| Carrots | — | — | Apr 24 – May 22 | Jul 5 – Jul 19 |
| Beets | — | — | Apr 24 – May 22 | Jul 19 – Aug 2 |
| Potatoes | — | — | Apr 24 – May 15 | — |
| Swiss Chard | — | — | May 1 – May 29 | Jul 19 – Aug 2 |
| Cilantro | — | — | May 1 – May 22 | Aug 2 – Aug 23 |
| Green Beans | — | — | May 22 – Jun 12 | Jul 12 – Jul 26 |
| Sweet Corn | — | — | May 22 – Jun 5 | — |
| Sweet Potatoes | — | May 29 – Jun 19 | — | — |
| Garlic | — | — | — | Sep 13 – Oct 18 |
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 Oral, SD weather station, 12 km away (elevation 2,959 ft (902 m)).
Frost dates near Smithwick
- Oral May 15 · Sep 27
- Oelrichs May 15 · Sep 30
- Buffalo Gap May 15 · Sep 27
- Hot Springs May 16 · Sep 27
- Fairburn May 15 · Sep 29
- Oglala May 7 · Oct 4
- Custer May 15 · Sep 29
- Pringle May 15 · Sep 29
- Edgemont May 23 · Sep 20
- Pine Ridge May 16 · Sep 27
Frequently asked questions
When is the last frost in Smithwick, SD?
The median last spring frost in Smithwick, SD is May 15. 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 Smithwick, SD?
The median first fall frost is September 27, with about a 10% chance of frost before September 11.
How long is the growing season in Smithwick, SD?
About 135 days between the median last spring frost and first fall frost.
What planting zone is Smithwick, SD?
Smithwick, SD is in USDA hardiness zone 5a.