Cosby, MO frost dates
How Cosby compares
- In 8 years out of 10, the last spring frost in Cosby falls between April 3 and May 1, a 28-day window. The first fall frost falls between October 4 and October 30.
- The median last frost is 5 days later than the Missouri median of Apr 12.
- Its 185-day growing season is longer than 17% of the 938 Missouri places with a regular frost season (state median 195 days).
- The last frost is 12 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 130 nights a year at or below 32°F.
- Compared with Saint Joseph, MO, 17 km away, the last frost here is 2 days earlier than there and the growing season is 4 days longer.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 3 |
| 50% (median) | April 17 |
| 10% (safe for tender plants) | May 1 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 4 |
| 50% (median) | October 19 |
| 90% (late) | October 30 |
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 Cosby, MO
Cosby, MO frost dates — last frost Apr 17, first frost Oct 19, zone 6a. whenisthelastfrost.com
When to plant vegetables in Cosby, MO
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 23 – Feb 6 | Mar 20 – Apr 3 | — | — |
| Peppers | Feb 6 – Feb 20 | May 1 – May 15 | — | — |
| Eggplant | Feb 6 – Feb 20 | May 1 – May 15 | — | — |
| Tomatoes | Feb 20 – Mar 6 | Apr 24 – May 8 | — | — |
| Lettuce | Feb 20 – Mar 6 | Mar 27 – Apr 10 | Mar 20 – Apr 24 | Aug 24 – Sep 21 |
| Kale | Feb 20 – Mar 6 | Mar 20 – Apr 3 | Mar 20 – Apr 3 | Aug 10 – Aug 31 |
| Broccoli | Feb 20 – Mar 6 | Apr 3 – Apr 17 | — | Jul 13 – Aug 3 |
| Cabbage | Feb 20 – Mar 6 | Mar 27 – Apr 10 | — | Jul 13 – Aug 3 |
| Cauliflower | Feb 20 – Mar 6 | Apr 3 – Apr 17 | — | Jul 13 – Aug 3 |
| Okra | Mar 6 – Mar 20 | May 8 – May 22 | May 8 – May 22 | — |
| Basil | Mar 6 – Mar 20 | Apr 24 – May 8 | — | — |
| Peas | — | — | Mar 6 – Mar 27 | Jul 27 – Aug 17 |
| Spinach | — | — | Mar 6 – Mar 27 | Aug 24 – Sep 14 |
| Radishes | — | — | Mar 13 – Apr 24 | Sep 7 – Sep 28 |
| Cucumbers | Mar 20 – Mar 27 | May 1 – May 8 | Apr 24 – May 8 | Aug 3 – Aug 17 |
| Zucchini & Summer Squash | Mar 20 – Mar 27 | — | Apr 24 – May 8 | Aug 10 – Aug 24 |
| Winter Squash & Pumpkins | Mar 20 – Mar 27 | — | Apr 24 – May 8 | — |
| Melons & Watermelon | Mar 20 – Mar 27 | May 1 – May 15 | — | — |
| Carrots | — | — | Mar 27 – Apr 24 | Jul 27 – Aug 10 |
| Beets | — | — | Mar 27 – Apr 24 | Aug 10 – Aug 24 |
| Potatoes | — | — | Mar 27 – Apr 17 | — |
| Swiss Chard | — | — | Apr 3 – May 1 | Aug 10 – Aug 24 |
| Cilantro | — | — | Apr 3 – Apr 24 | Aug 24 – Sep 14 |
| Green Beans | — | — | Apr 24 – May 15 | Aug 3 – Aug 17 |
| Sweet Corn | — | — | Apr 24 – May 8 | — |
| Sweet Potatoes | — | May 1 – May 22 | — | — |
| Garlic | — | — | — | Oct 5 – Nov 9 |
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 Cosby 2w, MO weather station, about 1 km away (elevation 909 ft (277 m)).
Frost dates near Cosby
- Helena Apr 17 · Oct 19
- Easton Apr 17 · Oct 19
- Savannah Apr 17 · Oct 19
- Clarksdale Apr 17 · Oct 19
- Amity Apr 19 · Oct 19
- Saint Joseph Apr 19 · Oct 17
- Stewartsville Apr 19 · Oct 19
- Union Star Apr 17 · Oct 19
- Amazonia Apr 19 · Oct 17
- Agency Apr 17 · Oct 19
Frequently asked questions
When is the last frost in Cosby, MO?
The median last spring frost in Cosby, MO is April 17. There is still about a 10% chance of frost after May 1, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Cosby, MO?
The median first fall frost is October 19, with about a 10% chance of frost before October 4.
How long is the growing season in Cosby, MO?
About 185 days between the median last spring frost and first fall frost.
What planting zone is Cosby, MO?
Cosby, MO is in USDA hardiness zone 6a.