Riley, IN frost dates
How Riley compares
- In 8 years out of 10, the last spring frost in Riley falls between March 31 and May 2, a 32-day window. The first fall frost falls between October 7 and November 6.
- The median last frost is 8 days earlier than the Indiana median of Apr 22.
- Its 193-day growing season is longer than 77% of the 733 Indiana places with a regular frost season (state median 182 days).
- The last frost is 15 days earlier than the zone 6a median of Apr 29. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 6a chart.
- The weather station records an average of 111 nights a year at or below 32°F.
- Compared with Terre Haute, IN, 12 km away, the last frost here is 1 day earlier than there and the growing season is 6 days longer.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | March 31 |
| 50% (median) | April 14 |
| 10% (safe for tender plants) | May 2 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 7 |
| 50% (median) | October 24 |
| 90% (late) | November 6 |
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, IN
Riley, IN frost dates — last frost Apr 14, first frost Oct 24, zone 6a. whenisthelastfrost.com
When to plant vegetables in Riley, IN
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 20 – Feb 3 | Mar 17 – Mar 31 | — | — |
| Peppers | Feb 3 – Feb 17 | Apr 28 – May 12 | — | — |
| Eggplant | Feb 3 – Feb 17 | Apr 28 – May 12 | — | — |
| Tomatoes | Feb 17 – Mar 3 | Apr 21 – May 5 | — | — |
| Lettuce | Feb 17 – Mar 3 | Mar 24 – Apr 7 | Mar 17 – Apr 21 | Aug 29 – Sep 26 |
| Kale | Feb 17 – Mar 3 | Mar 17 – Mar 31 | Mar 17 – Mar 31 | Aug 15 – Sep 5 |
| Broccoli | Feb 17 – Mar 3 | Mar 31 – Apr 14 | — | Jul 18 – Aug 8 |
| Cabbage | Feb 17 – Mar 3 | Mar 24 – Apr 7 | — | Jul 18 – Aug 8 |
| Cauliflower | Feb 17 – Mar 3 | Mar 31 – Apr 14 | — | Jul 18 – Aug 8 |
| Okra | Mar 3 – Mar 17 | May 5 – May 19 | May 5 – May 19 | — |
| Basil | Mar 3 – Mar 17 | Apr 21 – May 5 | — | — |
| Peas | — | — | Mar 3 – Mar 24 | Aug 1 – Aug 22 |
| Spinach | — | — | Mar 3 – Mar 24 | Aug 29 – Sep 19 |
| Radishes | — | — | Mar 10 – Apr 21 | Sep 12 – Oct 3 |
| Cucumbers | Mar 17 – Mar 24 | Apr 28 – May 5 | Apr 21 – May 5 | Aug 8 – Aug 22 |
| Zucchini & Summer Squash | Mar 17 – Mar 24 | — | Apr 21 – May 5 | Aug 15 – Aug 29 |
| Winter Squash & Pumpkins | Mar 17 – Mar 24 | — | Apr 21 – May 5 | — |
| Melons & Watermelon | Mar 17 – Mar 24 | Apr 28 – May 12 | — | — |
| Carrots | — | — | Mar 24 – Apr 21 | Aug 1 – Aug 15 |
| Beets | — | — | Mar 24 – Apr 21 | Aug 15 – Aug 29 |
| Potatoes | — | — | Mar 24 – Apr 14 | — |
| Swiss Chard | — | — | Mar 31 – Apr 28 | Aug 15 – Aug 29 |
| Cilantro | — | — | Mar 31 – Apr 21 | Aug 29 – Sep 19 |
| Green Beans | — | — | Apr 21 – May 12 | Aug 8 – Aug 22 |
| Sweet Corn | — | — | Apr 21 – May 5 | — |
| Sweet Potatoes | — | Apr 28 – May 19 | — | — |
| Garlic | — | — | — | Oct 10 – Nov 14 |
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 Terre Haute Caa Ap, IN weather station, 7 km away (elevation 574 ft (175 m)).
Frost dates near Riley
- Cory Apr 14 · Oct 24
- Pimento Apr 8 · Oct 27
- Terre Haute Apr 15 · Oct 19
- Seelyville Apr 14 · Oct 24
- Lewis Apr 8 · Oct 27
- Staunton Apr 14 · Oct 24
- Prairieton Apr 15 · Oct 19
- Centerpoint Apr 14 · Oct 24
- West Terre Haute Apr 15 · Oct 19
- Saint Mary Of The Woods Apr 15 · Oct 19
Frequently asked questions
When is the last frost in Riley, IN?
The median last spring frost in Riley, IN is April 14. There is still about a 10% chance of frost after May 2, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Riley, IN?
The median first fall frost is October 24, with about a 10% chance of frost before October 7.
How long is the growing season in Riley, IN?
About 193 days between the median last spring frost and first fall frost.
What planting zone is Riley, IN?
Riley, IN is in USDA hardiness zone 6a.