Frost dates for 66609Topeka, KS
The average last spring frost in Topeka is April 15 and the average first fall frost is October 21, giving a typical growing season of about 185 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 15
- Average first fall frost
- Oct 21
- Growing season
- 185 days
Safer after Apr 30 (1-in-10 risk)
Possible by Oct 5 (1-in-10 risk)
Last frost typically in 170 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 12 · Apr 27 · May 11 | Sep 27 · Oct 11 · Oct 25 | 165 days | 100% |
| Frost / freeze (32°F) | Apr 2 · Apr 15 · Apr 30 | Oct 5 · Oct 21 · Nov 2 | 185 days | 100% |
| Hard freeze (28°F) | Mar 21 · Apr 5 · Apr 21 | Oct 17 · Oct 31 · Nov 12 | 205 days | 100% |
Planting calendar for Topeka
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 15 – May 21 |
| Tomatoes | Transplant outdoors | May 1 – Jul 1 |
| Peppers | Start seeds indoors | Mar 15 – Apr 15 |
| Peppers | Transplant outdoors | May 15 – Jun 15 |
| Eggplant | Start seeds indoors | Apr 1 – Apr 30 |
| Eggplant | Transplant outdoors | May 15 – Jun 15 |
| Cucumbers | Sow outdoors | May 15 – Jul 11 |
| Summer squash | Sow outdoors | May 1 – Jun 15 |
| Winter squash & pumpkins | Sow outdoors | May 15 – Jun 15 |
| Snap beans | Sow outdoors | May 1 – Aug 3 |
| Sweet corn | Sow outdoors | May 1 – Jul 1 |
| Watermelon & cantaloupe | Sow outdoors | May 15 – Jun 15 |
| Okra | Sow outdoors | May 8 – May 31 |
| Peas | Sow outdoors (spring) | Mar 15 – Apr 30 |
| Potatoes | Plant outdoors (spring) | Mar 15 – May 15 |
| Onions | Start seeds indoors (spring) | Feb 1 – Feb 28 |
| Onions | Transplant outdoors (spring) | Apr 1 – Apr 30 |
| Broccoli | Start seeds indoors (spring) | Feb 25 – Mar 31 |
| Broccoli | Transplant outdoors (spring) | Apr 1 – Apr 30 |
| Broccoli | Start seeds indoors (fall) | Jun 21 – Jul 1 |
| Broccoli | Transplant outdoors (fall) | Jul 21 – Aug 1 |
| Cabbage | Start seeds indoors (spring) | Feb 15 – Mar 15 |
| Cabbage | Transplant outdoors (spring) | Mar 15 – Apr 15 |
| Cabbage | Start seeds indoors (fall) | Jun 11 – Jul 11 |
| Cabbage | Transplant outdoors (fall) | Jul 11 – Aug 11 |
| Leaf lettuce | Sow outdoors (spring) | Mar 15 – May 31 |
| Leaf lettuce | Sow outdoors (fall) | Jul 11 – Aug 27 |
| Spinach | Sow outdoors (spring) | Mar 8 – Apr 21 |
| Spinach | Sow outdoors (fall) | Jul 28 – Sep 1 |
| Radishes | Sow outdoors (spring) | Mar 15 – May 5 |
| Radishes | Sow outdoors (fall) | Jul 11 – Sep 11 |
| Kale | Sow outdoors (spring) | Apr 1 – Apr 21 |
| Kale | Sow outdoors (fall) | Jul 4 – Aug 11 |
| Carrots | Sow outdoors (spring) | Apr 15 – May 31 |
| Carrots | Sow outdoors (fall) | Jun 11 – Jul 27 |
| Garlic | Plant outdoors (fall) | Oct 11 – Nov 11 |
Where these dates come from
ZIP code 66609 is matched to the NOAA station Topeka Forbes Fld, KS, 4.6 km away, at 1,067 ft elevation (76 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Topeka Forbes Fld, KS (used) | 1,067 ft | Apr 15 | Oct 21 |
| Topeka - Nws, KS | 880 ft | Apr 16 | Oct 22 |
| Topeka Muni Ap, KS | 876 ft | Apr 12 | Oct 23 |
| Perry Lake, KS | 957 ft | Apr 13 | Oct 24 |
Frost dates near Topeka
- Topeka, KS 66605 · last Apr 12, first Oct 23
- Berryton, KS 66409 · last Apr 15, first Oct 21
- Wakarusa, KS 66546 · last Apr 15, first Oct 21
- Tecumseh, KS 66542 · last Apr 12, first Oct 23
- Auburn, KS 66402 · last Apr 15, first Oct 21
- Grantville, KS 66429 · last Apr 12, first Oct 23
- Carbondale, KS 66414 · last Apr 15, first Oct 21
- Lecompton, KS 66050 · last Apr 15, first Oct 22
Frequently asked questions
- When is the last frost in Topeka, KS?
- For ZIP code 66609, the average last spring frost (32°F) is April 15, based on NOAA 1991-2020 climate normals for the Topeka Forbes Fld, KS weather station. There is a 1-in-10 chance of a frost after April 30.
- When is the first frost in Topeka, KS?
- The average first fall frost (32°F) is October 21. There is a 1-in-10 chance of frost by October 5, so tender plants are at risk from that point on.
- How long is the growing season in 66609?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 185 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.