Frost dates for 66416Circleville, KS
The average last spring frost in Circleville is April 24 and the average first fall frost is October 14, giving a typical growing season of about 172 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 24
- Average first fall frost
- Oct 14
- Growing season
- 172 days
Safer after May 7 (1-in-10 risk)
Possible by Sep 29 (1-in-10 risk)
Last frost typically in 179 days
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | Apr 20 · May 3 · May 17 | Sep 20 · Oct 4 · Oct 17 | 155 days | 100% |
| Frost / freeze (32°F) | Apr 10 · Apr 24 · May 7 | Sep 29 · Oct 14 · Oct 26 | 172 days | 100% |
| Hard freeze (28°F) | Mar 31 · Apr 13 · Apr 28 | Oct 10 · Oct 24 · Nov 5 | 192 days | 100% |
Planting calendar for Circleville
Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.
| Crop | Task | Window |
|---|---|---|
| Tomatoes | Start seeds indoors | Mar 24 – May 30 |
| Tomatoes | Transplant outdoors | May 10 – Jun 24 |
| Peppers | Start seeds indoors | Mar 24 – Apr 24 |
| Peppers | Transplant outdoors | May 24 – Jun 24 |
| Eggplant | Start seeds indoors | Apr 10 – May 9 |
| Eggplant | Transplant outdoors | May 24 – Jun 24 |
| Cucumbers | Sow outdoors | May 24 – Jul 4 |
| Summer squash | Sow outdoors | May 10 – Jun 24 |
| Winter squash & pumpkins | Sow outdoors | May 24 – Jun 24 |
| Snap beans | Sow outdoors | May 10 – Jul 27 |
| Sweet corn | Sow outdoors | May 10 – Jun 24 |
| Watermelon & cantaloupe | Sow outdoors | May 24 – Jun 24 |
| Okra | Sow outdoors | May 17 – Jun 9 |
| Peas | Sow outdoors (spring) | Mar 24 – May 9 |
| Potatoes | Plant outdoors (spring) | Mar 24 – May 24 |
| Onions | Start seeds indoors (spring) | Feb 10 – Mar 9 |
| Onions | Transplant outdoors (spring) | Apr 10 – May 9 |
| Broccoli | Start seeds indoors (spring) | Mar 6 – Apr 9 |
| Broccoli | Transplant outdoors (spring) | Apr 10 – May 9 |
| Broccoli | Start seeds indoors (fall) | Jun 14 – Jun 24 |
| Broccoli | Transplant outdoors (fall) | Jul 14 – Jul 25 |
| Cabbage | Start seeds indoors (spring) | Feb 24 – Mar 24 |
| Cabbage | Transplant outdoors (spring) | Mar 24 – Apr 24 |
| Cabbage | Start seeds indoors (fall) | Jun 4 – Jul 4 |
| Cabbage | Transplant outdoors (fall) | Jul 4 – Aug 4 |
| Leaf lettuce | Sow outdoors (spring) | Mar 24 – Jun 9 |
| Leaf lettuce | Sow outdoors (fall) | Jul 4 – Aug 20 |
| Spinach | Sow outdoors (spring) | Mar 17 – Apr 30 |
| Spinach | Sow outdoors (fall) | Jul 21 – Aug 25 |
| Radishes | Sow outdoors (spring) | Mar 24 – May 14 |
| Radishes | Sow outdoors (fall) | Jul 4 – Sep 4 |
| Kale | Sow outdoors (spring) | Apr 10 – Apr 30 |
| Kale | Sow outdoors (fall) | Jun 27 – Aug 4 |
| Carrots | Sow outdoors (spring) | Apr 24 – Jun 9 |
| Carrots | Sow outdoors (fall) | Jun 4 – Jul 20 |
| Garlic | Plant outdoors (fall) | Oct 4 – Nov 4 |
Where these dates come from
ZIP code 66416 is matched to the NOAA station Holton, KS, 10.5 km away, at 1,050 ft elevation (151 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Holton, KS (used) | 1,050 ft | Apr 24 | Oct 14 |
| Centralia, KS | 1,320 ft | Apr 19 | Oct 19 |
| Horton, KS | 1,032 ft | Apr 18 | Oct 17 |
| Valley Falls 3 Sw, KS | 1,051 ft | Apr 10 | Oct 29 |
Frost dates near Circleville
- Soldier, KS 66540 · last Apr 24, first Oct 14
- Holton, KS 66436 · last Apr 24, first Oct 14
- Wetmore, KS 66550 · last Apr 24, first Oct 14
- Netawaka, KS 66516 · last Apr 24, first Oct 14
- Goff, KS 66428 · last Apr 19, first Oct 19
- Havensville, KS 66432 · last Apr 24, first Oct 14
- Corning, KS 66417 · last Apr 19, first Oct 19
- Whiting, KS 66552 · last Apr 18, first Oct 17
Frequently asked questions
- When is the last frost in Circleville, KS?
- For ZIP code 66416, the average last spring frost (32°F) is April 24, based on NOAA 1991-2020 climate normals for the Holton, KS weather station. There is a 1-in-10 chance of a frost after May 7.
- When is the first frost in Circleville, KS?
- The average first fall frost (32°F) is October 14. There is a 1-in-10 chance of frost by September 29, so tender plants are at risk from that point on.
- How long is the growing season in 66416?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 172 days long.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.