Grenville, SD frost dates
Last spring frostMay 1median date
First fall frostOct 12median date
Growing season164 daysfrost-free
Hardiness zone4bZone 4b
How Grenville compares
- In 8 years out of 10, the last spring frost in Grenville falls between April 17 and May 12, a 25-day window. The first fall frost falls between September 30 and October 26.
- The median last frost is 5 days earlier than the South Dakota median of May 6.
- Its 164-day growing season is longer than 94% of the 363 South Dakota places with a regular frost season (state median 149 days).
- The last frost is 7 days earlier 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 166 nights a year at or below 32°F.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 17 |
| 50% (median) | May 1 |
| 10% (safe for tender plants) | May 12 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 30 |
| 50% (median) | October 12 |
| 90% (late) | October 26 |
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 Grenville, SD
Grenville, SD frost dates — last frost May 1, first frost Oct 12, zone 4b. whenisthelastfrost.com
Crop
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Start indoors: Feb 6 to Feb 20Transplant outside: Apr 3 to Apr 17
Start indoors: Feb 20 to Mar 6Transplant outside: May 15 to May 29
Start indoors: Feb 20 to Mar 6Transplant outside: May 15 to May 29
Start indoors: Mar 6 to Mar 20Transplant outside: May 8 to May 22
Start indoors: Mar 6 to Mar 20Transplant outside: Apr 10 to Apr 24Sow outdoors: Apr 3 to May 8Plant for fall: Aug 17 to Sep 14
Start indoors: Mar 6 to Mar 20Transplant outside: Apr 3 to Apr 17Sow outdoors: Apr 3 to Apr 17Plant for fall: Aug 3 to Aug 24
Start indoors: Mar 6 to Mar 20Transplant outside: Apr 17 to May 1Plant for fall: Jul 6 to Jul 27
Start indoors: Mar 6 to Mar 20Transplant outside: Apr 10 to Apr 24Plant for fall: Jul 6 to Jul 27
Start indoors: Mar 6 to Mar 20Transplant outside: Apr 17 to May 1Plant for fall: Jul 6 to Jul 27
Start indoors: Mar 20 to Apr 3Transplant outside: May 22 to Jun 5Sow outdoors: May 22 to Jun 5
Start indoors: Mar 20 to Apr 3Transplant outside: May 8 to May 22
Sow outdoors: Mar 20 to Apr 10Plant for fall: Jul 20 to Aug 10
Sow outdoors: Mar 20 to Apr 10Plant for fall: Aug 17 to Sep 7
Sow outdoors: Mar 27 to May 8Plant for fall: Aug 31 to Sep 21
Start indoors: Apr 3 to Apr 10Transplant outside: May 15 to May 22Sow outdoors: May 8 to May 22Plant for fall: Jul 27 to Aug 10
Start indoors: Apr 3 to Apr 10Sow outdoors: May 8 to May 22Plant for fall: Aug 3 to Aug 17
Start indoors: Apr 3 to Apr 10Sow outdoors: May 8 to May 22
Start indoors: Apr 3 to Apr 10Transplant outside: May 15 to May 29
Sow outdoors: Apr 10 to May 8Plant for fall: Jul 20 to Aug 3
Sow outdoors: Apr 10 to May 8Plant for fall: Aug 3 to Aug 17
Sow outdoors: Apr 10 to May 1
Sow outdoors: Apr 17 to May 15Plant for fall: Aug 3 to Aug 17
Sow outdoors: Apr 17 to May 8Plant for fall: Aug 17 to Sep 7
Sow outdoors: May 8 to May 29Plant for fall: Jul 27 to Aug 10
Sow outdoors: May 8 to May 22
Transplant outside: May 15 to Jun 5
Plant for fall: Sep 28 to Nov 2
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Grenville, SD
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 6 – Feb 20 | Apr 3 – Apr 17 | — | — |
| Peppers | Feb 20 – Mar 6 | May 15 – May 29 | — | — |
| Eggplant | Feb 20 – Mar 6 | May 15 – May 29 | — | — |
| Tomatoes | Mar 6 – Mar 20 | May 8 – May 22 | — | — |
| Lettuce | Mar 6 – Mar 20 | Apr 10 – Apr 24 | Apr 3 – May 8 | Aug 17 – Sep 14 |
| Kale | Mar 6 – Mar 20 | Apr 3 – Apr 17 | Apr 3 – Apr 17 | Aug 3 – Aug 24 |
| Broccoli | Mar 6 – Mar 20 | Apr 17 – May 1 | — | Jul 6 – Jul 27 |
| Cabbage | Mar 6 – Mar 20 | Apr 10 – Apr 24 | — | Jul 6 – Jul 27 |
| Cauliflower | Mar 6 – Mar 20 | Apr 17 – May 1 | — | Jul 6 – Jul 27 |
| Okra | Mar 20 – Apr 3 | May 22 – Jun 5 | May 22 – Jun 5 | — |
| Basil | Mar 20 – Apr 3 | May 8 – May 22 | — | — |
| Peas | — | — | Mar 20 – Apr 10 | Jul 20 – Aug 10 |
| Spinach | — | — | Mar 20 – Apr 10 | Aug 17 – Sep 7 |
| Radishes | — | — | Mar 27 – May 8 | Aug 31 – Sep 21 |
| Cucumbers | Apr 3 – Apr 10 | May 15 – May 22 | May 8 – May 22 | Jul 27 – Aug 10 |
| Zucchini & Summer Squash | Apr 3 – Apr 10 | — | May 8 – May 22 | Aug 3 – Aug 17 |
| Winter Squash & Pumpkins | Apr 3 – Apr 10 | — | May 8 – May 22 | — |
| Melons & Watermelon | Apr 3 – Apr 10 | May 15 – May 29 | — | — |
| Carrots | — | — | Apr 10 – May 8 | Jul 20 – Aug 3 |
| Beets | — | — | Apr 10 – May 8 | Aug 3 – Aug 17 |
| Potatoes | — | — | Apr 10 – May 1 | — |
| Swiss Chard | — | — | Apr 17 – May 15 | Aug 3 – Aug 17 |
| Cilantro | — | — | Apr 17 – May 8 | Aug 17 – Sep 7 |
| Green Beans | — | — | May 8 – May 29 | Jul 27 – Aug 10 |
| Sweet Corn | — | — | May 8 – May 22 | — |
| Sweet Potatoes | — | May 15 – Jun 5 | — | — |
| Garlic | — | — | — | Sep 28 – Nov 2 |
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 Waubay Natl Wild Life, SD weather station, 10 km away (elevation 1,827 ft (557 m)).
Frost dates near Grenville
- Eden May 2 · Oct 9
- Waubay May 1 · Oct 12
- Roslyn May 1 · Oct 12
- Lake City May 2 · Oct 9
- Peever May 9 · Sep 28
- Sisseton May 4 · Oct 3
- Summit May 14 · Sep 28
- Webster May 4 · Oct 6
- Ortley May 14 · Sep 28
- Wilmot May 5 · Oct 1
Frequently asked questions
When is the last frost in Grenville, SD?
The median last spring frost in Grenville, SD is May 1. There is still about a 10% chance of frost after May 12, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Grenville, SD?
The median first fall frost is October 12, with about a 10% chance of frost before September 30.
How long is the growing season in Grenville, SD?
About 164 days between the median last spring frost and first fall frost.
What planting zone is Grenville, SD?
Grenville, SD is in USDA hardiness zone 4b.