Riley, KS frost dates
Last spring frostApr 22median date
First fall frostOct 20median date
Growing season181 daysfrost-free
Hardiness zone6bZone 6b
How Riley compares
- In 8 years out of 10, the last spring frost in Riley falls between April 8 and May 5, a 27-day window. The first fall frost falls between October 4 and November 1.
- The median last frost is 4 days later than the Kansas median of Apr 18.
- Its 181-day growing season is longer than 31% of the 632 Kansas places with a regular frost season (state median 187 days).
- The last frost is typical for zone 6b, where the median is Apr 22.
- The weather station records an average of 134 nights a year at or below 32°F.
- Riley shares its weather station with Manhattan, KS, 19 km away, so the two have the same frost dates.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 8 |
| 50% (median) | April 22 |
| 10% (safe for tender plants) | May 5 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 4 |
| 50% (median) | October 20 |
| 90% (late) | November 1 |
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 Riley, KS
Riley, KS frost dates — last frost Apr 22, first frost Oct 20, zone 6b. whenisthelastfrost.com
Crop
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Start indoors: Jan 28 to Feb 11Transplant outside: Mar 25 to Apr 8
Start indoors: Feb 11 to Feb 25Transplant outside: May 6 to May 20
Start indoors: Feb 11 to Feb 25Transplant outside: May 6 to May 20
Start indoors: Feb 25 to Mar 11Transplant outside: Apr 29 to May 13
Start indoors: Feb 25 to Mar 11Transplant outside: Apr 1 to Apr 15Sow outdoors: Mar 25 to Apr 29Plant for fall: Aug 25 to Sep 22
Start indoors: Feb 25 to Mar 11Transplant outside: Mar 25 to Apr 8Sow outdoors: Mar 25 to Apr 8Plant for fall: Aug 11 to Sep 1
Start indoors: Feb 25 to Mar 11Transplant outside: Apr 8 to Apr 22Plant for fall: Jul 14 to Aug 4
Start indoors: Feb 25 to Mar 11Transplant outside: Apr 1 to Apr 15Plant for fall: Jul 14 to Aug 4
Start indoors: Feb 25 to Mar 11Transplant outside: Apr 8 to Apr 22Plant for fall: Jul 14 to Aug 4
Start indoors: Mar 11 to Mar 25Transplant outside: May 13 to May 27Sow outdoors: May 13 to May 27
Start indoors: Mar 11 to Mar 25Transplant outside: Apr 29 to May 13
Sow outdoors: Mar 11 to Apr 1Plant for fall: Jul 28 to Aug 18
Sow outdoors: Mar 11 to Apr 1Plant for fall: Aug 25 to Sep 15
Sow outdoors: Mar 18 to Apr 29Plant for fall: Sep 8 to Sep 29
Start indoors: Mar 25 to Apr 1Transplant outside: May 6 to May 13Sow outdoors: Apr 29 to May 13Plant for fall: Aug 4 to Aug 18
Start indoors: Mar 25 to Apr 1Sow outdoors: Apr 29 to May 13Plant for fall: Aug 11 to Aug 25
Start indoors: Mar 25 to Apr 1Sow outdoors: Apr 29 to May 13
Start indoors: Mar 25 to Apr 1Transplant outside: May 6 to May 20
Sow outdoors: Apr 1 to Apr 29Plant for fall: Jul 28 to Aug 11
Sow outdoors: Apr 1 to Apr 29Plant for fall: Aug 11 to Aug 25
Sow outdoors: Apr 1 to Apr 22
Sow outdoors: Apr 8 to May 6Plant for fall: Aug 11 to Aug 25
Sow outdoors: Apr 8 to Apr 29Plant for fall: Aug 25 to Sep 15
Sow outdoors: Apr 29 to May 20Plant for fall: Aug 4 to Aug 18
Sow outdoors: Apr 29 to May 13
Transplant outside: May 6 to May 27
Plant for fall: Oct 6 to Nov 10
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Riley, KS
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 28 – Feb 11 | Mar 25 – Apr 8 | — | — |
| Peppers | Feb 11 – Feb 25 | May 6 – May 20 | — | — |
| Eggplant | Feb 11 – Feb 25 | May 6 – May 20 | — | — |
| Tomatoes | Feb 25 – Mar 11 | Apr 29 – May 13 | — | — |
| Lettuce | Feb 25 – Mar 11 | Apr 1 – Apr 15 | Mar 25 – Apr 29 | Aug 25 – Sep 22 |
| Kale | Feb 25 – Mar 11 | Mar 25 – Apr 8 | Mar 25 – Apr 8 | Aug 11 – Sep 1 |
| Broccoli | Feb 25 – Mar 11 | Apr 8 – Apr 22 | — | Jul 14 – Aug 4 |
| Cabbage | Feb 25 – Mar 11 | Apr 1 – Apr 15 | — | Jul 14 – Aug 4 |
| Cauliflower | Feb 25 – Mar 11 | Apr 8 – Apr 22 | — | Jul 14 – Aug 4 |
| Okra | Mar 11 – Mar 25 | May 13 – May 27 | May 13 – May 27 | — |
| Basil | Mar 11 – Mar 25 | Apr 29 – May 13 | — | — |
| Peas | — | — | Mar 11 – Apr 1 | Jul 28 – Aug 18 |
| Spinach | — | — | Mar 11 – Apr 1 | Aug 25 – Sep 15 |
| Radishes | — | — | Mar 18 – Apr 29 | Sep 8 – Sep 29 |
| Cucumbers | Mar 25 – Apr 1 | May 6 – May 13 | Apr 29 – May 13 | Aug 4 – Aug 18 |
| Zucchini & Summer Squash | Mar 25 – Apr 1 | — | Apr 29 – May 13 | Aug 11 – Aug 25 |
| Winter Squash & Pumpkins | Mar 25 – Apr 1 | — | Apr 29 – May 13 | — |
| Melons & Watermelon | Mar 25 – Apr 1 | May 6 – May 20 | — | — |
| Carrots | — | — | Apr 1 – Apr 29 | Jul 28 – Aug 11 |
| Beets | — | — | Apr 1 – Apr 29 | Aug 11 – Aug 25 |
| Potatoes | — | — | Apr 1 – Apr 22 | — |
| Swiss Chard | — | — | Apr 8 – May 6 | Aug 11 – Aug 25 |
| Cilantro | — | — | Apr 8 – Apr 29 | Aug 25 – Sep 15 |
| Green Beans | — | — | Apr 29 – May 20 | Aug 4 – Aug 18 |
| Sweet Corn | — | — | Apr 29 – May 13 | — |
| Sweet Potatoes | — | May 6 – May 27 | — | — |
| Garlic | — | — | — | Oct 6 – Nov 10 |
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 Tuttle Creek Lake, KS weather station, 20 km away (elevation 1,060 ft (323 m)).
Frost dates near Riley
- Leonardville Apr 19 · Oct 19
- Milford Apr 12 · Oct 26
- Manhattan Apr 22 · Oct 20
- Wakefield Apr 19 · Oct 19
- Randolph Apr 22 · Oct 20
- Ogden Apr 21 · Oct 16
- Olsburg Apr 22 · Oct 20
- Green Apr 19 · Oct 19
- Fort Riley Apr 12 · Oct 26
- Clay Center Apr 19 · Oct 19
Frequently asked questions
When is the last frost in Riley, KS?
The median last spring frost in Riley, KS is April 22. There is still about a 10% chance of frost after May 5, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Riley, KS?
The median first fall frost is October 20, with about a 10% chance of frost before October 4.
How long is the growing season in Riley, KS?
About 181 days between the median last spring frost and first fall frost.
What planting zone is Riley, KS?
Riley, KS is in USDA hardiness zone 6b.