Frost dates for 63357Marthasville, MO
The average last spring frost in Marthasville is April 11 and the average first fall frost is October 23, giving a typical growing season of about 194 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 11
- Average first fall frost
- Oct 23
- Growing season
- 194 days
Safer after Apr 28 (1-in-10 risk)
Possible by Oct 9 (1-in-10 risk)
Last frost typically in 160 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 8 · Apr 22 · May 8 | Sep 30 · Oct 13 · Oct 26 | 172 days | 100% |
| Frost / freeze (32°F) | Mar 26 · Apr 11 · Apr 28 | Oct 9 · Oct 23 · Nov 5 | 194 days | 100% |
| Hard freeze (28°F) | Mar 12 · Mar 31 · Apr 15 | Oct 21 · Nov 3 · Nov 18 | 217 days | 100% |
Planting calendar for Marthasville
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 11 – May 17 |
| Tomatoes | Transplant outdoors | Apr 27 – Jul 3 |
| Peppers | Start seeds indoors | Mar 11 – Apr 11 |
| Peppers | Transplant outdoors | May 11 – Jun 11 |
| Eggplant | Start seeds indoors | Mar 28 – Apr 26 |
| Eggplant | Transplant outdoors | May 11 – Jun 11 |
| Cucumbers | Sow outdoors | May 11 – Jul 13 |
| Summer squash | Sow outdoors | Apr 27 – Jun 11 |
| Winter squash & pumpkins | Sow outdoors | May 11 – Jun 11 |
| Snap beans | Sow outdoors | Apr 27 – Aug 5 |
| Sweet corn | Sow outdoors | Apr 27 – Jul 3 |
| Watermelon & cantaloupe | Sow outdoors | May 11 – Jun 11 |
| Okra | Sow outdoors | May 4 – May 27 |
| Peas | Sow outdoors (spring) | Mar 11 – Apr 26 |
| Potatoes | Plant outdoors (spring) | Mar 11 – May 11 |
| Onions | Start seeds indoors (spring) | Jan 28 – Feb 24 |
| Onions | Transplant outdoors (spring) | Mar 28 – Apr 26 |
| Broccoli | Start seeds indoors (spring) | Feb 21 – Mar 27 |
| Broccoli | Transplant outdoors (spring) | Mar 28 – Apr 26 |
| Broccoli | Start seeds indoors (fall) | Jun 23 – Jul 3 |
| Broccoli | Transplant outdoors (fall) | Jul 23 – Aug 3 |
| Cabbage | Start seeds indoors (spring) | Feb 11 – Mar 11 |
| Cabbage | Transplant outdoors (spring) | Mar 11 – Apr 11 |
| Cabbage | Start seeds indoors (fall) | Jun 13 – Jul 13 |
| Cabbage | Transplant outdoors (fall) | Jul 13 – Aug 13 |
| Leaf lettuce | Sow outdoors (spring) | Mar 11 – May 27 |
| Leaf lettuce | Sow outdoors (fall) | Jul 13 – Aug 29 |
| Spinach | Sow outdoors (spring) | Mar 4 – Apr 17 |
| Spinach | Sow outdoors (fall) | Jul 30 – Sep 3 |
| Radishes | Sow outdoors (spring) | Mar 11 – May 1 |
| Radishes | Sow outdoors (fall) | Jul 13 – Sep 13 |
| Kale | Sow outdoors (spring) | Mar 28 – Apr 17 |
| Kale | Sow outdoors (fall) | Jul 6 – Aug 13 |
| Carrots | Sow outdoors (spring) | Apr 11 – May 27 |
| Carrots | Sow outdoors (fall) | Jun 13 – Jul 29 |
| Garlic | Plant outdoors (fall) | Oct 13 – Nov 13 |
Where these dates come from
ZIP code 63357 is matched to the NOAA station Union, MO, 26.3 km away, at 540 ft elevation (18 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Union, MO (used) | 540 ft | Apr 11 | Oct 23 |
| Washington, MO | 487 ft | Apr 8 | Oct 25 |
| Warrenton 1 N, MO | 827 ft | Apr 14 | Oct 23 |
| Rosebud, MO | 730 ft | Apr 27 | Oct 13 |
Frost dates near Marthasville
- Treloar, MO 63378 · last Apr 11, first Oct 23
- New Haven, MO 63068 · last Apr 11, first Oct 23
- Dutzow, MO 63342 · last Apr 11, first Oct 23
- Berger, MO 63014 · last Apr 27, first Oct 13
- Washington, MO 63090 · last Apr 11, first Oct 23
- Warrenton, MO 63383 · last Apr 14, first Oct 23
- Truesdale, MO 63380 · last Apr 14, first Oct 23
- Wright City, MO 63390 · last Apr 14, first Oct 23
Frequently asked questions
- When is the last frost in Marthasville, MO?
- For ZIP code 63357, the average last spring frost (32°F) is April 11, based on NOAA 1991-2020 climate normals for the Union, MO weather station. There is a 1-in-10 chance of a frost after April 28.
- When is the first frost in Marthasville, MO?
- The average first fall frost (32°F) is October 23. There is a 1-in-10 chance of frost by October 9, so tender plants are at risk from that point on.
- How long is the growing season in 63357?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 194 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.