Frost dates for 64089Smithville, MO
The average last spring frost in Smithville is April 18 and the average first fall frost is October 20, giving a typical growing season of about 183 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 18
- Average first fall frost
- Oct 20
- Growing season
- 183 days
Safer after May 3 (1-in-10 risk)
Possible by Oct 5 (1-in-10 risk)
Last frost typically in 166 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 14 · Apr 28 · May 13 | Sep 25 · Oct 10 · Oct 23 | 164 days | 100% |
| Frost / freeze (32°F) | Apr 4 · Apr 18 · May 3 | Oct 5 · Oct 20 · Nov 1 | 183 days | 100% |
| Hard freeze (28°F) | Mar 23 · Apr 7 · Apr 23 | Oct 15 · Oct 29 · Nov 11 | 204 days | 100% |
Planting calendar for Smithville
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 18 – May 24 |
| Tomatoes | Transplant outdoors | May 4 – Jun 30 |
| Peppers | Start seeds indoors | Mar 18 – Apr 18 |
| Peppers | Transplant outdoors | May 18 – Jun 18 |
| Eggplant | Start seeds indoors | Apr 4 – May 3 |
| Eggplant | Transplant outdoors | May 18 – Jun 18 |
| Cucumbers | Sow outdoors | May 18 – Jul 10 |
| Summer squash | Sow outdoors | May 4 – Jun 18 |
| Winter squash & pumpkins | Sow outdoors | May 18 – Jun 18 |
| Snap beans | Sow outdoors | May 4 – Aug 2 |
| Sweet corn | Sow outdoors | May 4 – Jun 30 |
| Watermelon & cantaloupe | Sow outdoors | May 18 – Jun 18 |
| Okra | Sow outdoors | May 11 – Jun 3 |
| Peas | Sow outdoors (spring) | Mar 18 – May 3 |
| Potatoes | Plant outdoors (spring) | Mar 18 – May 18 |
| Onions | Start seeds indoors (spring) | Feb 4 – Mar 3 |
| Onions | Transplant outdoors (spring) | Apr 4 – May 3 |
| Broccoli | Start seeds indoors (spring) | Feb 28 – Apr 3 |
| Broccoli | Transplant outdoors (spring) | Apr 4 – May 3 |
| Broccoli | Start seeds indoors (fall) | Jun 20 – Jun 30 |
| Broccoli | Transplant outdoors (fall) | Jul 20 – Jul 31 |
| Cabbage | Start seeds indoors (spring) | Feb 18 – Mar 18 |
| Cabbage | Transplant outdoors (spring) | Mar 18 – Apr 18 |
| Cabbage | Start seeds indoors (fall) | Jun 10 – Jul 10 |
| Cabbage | Transplant outdoors (fall) | Jul 10 – Aug 10 |
| Leaf lettuce | Sow outdoors (spring) | Mar 18 – Jun 3 |
| Leaf lettuce | Sow outdoors (fall) | Jul 10 – Aug 26 |
| Spinach | Sow outdoors (spring) | Mar 11 – Apr 24 |
| Spinach | Sow outdoors (fall) | Jul 27 – Aug 31 |
| Radishes | Sow outdoors (spring) | Mar 18 – May 8 |
| Radishes | Sow outdoors (fall) | Jul 10 – Sep 10 |
| Kale | Sow outdoors (spring) | Apr 4 – Apr 24 |
| Kale | Sow outdoors (fall) | Jul 3 – Aug 10 |
| Carrots | Sow outdoors (spring) | Apr 18 – Jun 3 |
| Carrots | Sow outdoors (fall) | Jun 10 – Jul 26 |
| Garlic | Plant outdoors (fall) | Oct 10 – Nov 10 |
Where these dates come from
ZIP code 64089 is matched to the NOAA station Smithville Lake, MO, 0.8 km away, at 904 ft elevation (54 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Smithville Lake, MO (used) | 904 ft | Apr 18 | Oct 20 |
| Kansas City Intl Ap, MO | 1,005 ft | Apr 13 | Oct 24 |
| Kearney 3E, MO | 840 ft | Apr 19 | Oct 17 |
| Kansas City Downtown Ap, MO | 742 ft | Apr 4 | Nov 2 |
Frost dates near Smithville
- Kansas City, MO 64166 · last Apr 18, first Oct 20
- Trimble, MO 64492 · last Apr 18, first Oct 20
- Edgerton, MO 64444 · last Apr 18, first Oct 20
- Holt, MO 64048 · last Apr 19, first Oct 17
- Kearney, MO 64060 · last Apr 19, first Oct 17
- Camden Point, MO 64018 · last Apr 18, first Oct 20
- Platte City, MO 64079 · last Apr 12, first Oct 27
- Liberty, MO 64068 · last Apr 19, first Oct 17
Frequently asked questions
- When is the last frost in Smithville, MO?
- For ZIP code 64089, the average last spring frost (32°F) is April 18, based on NOAA 1991-2020 climate normals for the Smithville Lake, MO weather station. There is a 1-in-10 chance of a frost after May 3.
- When is the first frost in Smithville, MO?
- The average first fall frost (32°F) is October 20. 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 64089?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 183 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.