Frost dates for 63138 — Saint Louis, MO
How Saint Louis compares
- In 8 years out of 10, the last spring frost in Saint Louis falls between March 18 and April 19, a 32-day window. The first fall frost falls between October 25 and November 21.
- The median last frost is 8 days earlier than the Missouri median of Apr 12.
- Its 215-day growing season is longer than 93% of the 938 Missouri places with a regular frost season (state median 195 days).
- The last frost is 12 days earlier than the zone 7a median of Apr 16. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 7a chart.
- The weather station records an average of 85 nights a year at or below 32°F.
- Compared with Florissant, MO, 12 km away, the last frost here is 2 days later than there and the growing season is 1 day shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | March 18 |
| 50% (median) | April 4 |
| 10% (safe for tender plants) | April 19 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 25 |
| 50% (median) | November 5 |
| 90% (late) | November 21 |
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 Saint Louis, MO
Frost dates for 63138 — Saint Louis, MO — last frost Apr 4, first frost Nov 5, zone 7a. whenisthelastfrost.com
When to plant vegetables in Saint Louis, MO
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 10 – Jan 24 | Mar 7 – Mar 21 | — | — |
| Peppers | Jan 24 – Feb 7 | Apr 18 – May 2 | — | — |
| Eggplant | Jan 24 – Feb 7 | Apr 18 – May 2 | — | — |
| Tomatoes | Feb 7 – Feb 21 | Apr 11 – Apr 25 | — | — |
| Lettuce | Feb 7 – Feb 21 | Mar 14 – Mar 28 | Mar 7 – Apr 11 | Sep 10 – Oct 8 |
| Kale | Feb 7 – Feb 21 | Mar 7 – Mar 21 | Mar 7 – Mar 21 | Aug 27 – Sep 17 |
| Broccoli | Feb 7 – Feb 21 | Mar 21 – Apr 4 | — | Jul 30 – Aug 20 |
| Cabbage | Feb 7 – Feb 21 | Mar 14 – Mar 28 | — | Jul 30 – Aug 20 |
| Cauliflower | Feb 7 – Feb 21 | Mar 21 – Apr 4 | — | Jul 30 – Aug 20 |
| Okra | Feb 21 – Mar 7 | Apr 25 – May 9 | Apr 25 – May 9 | — |
| Basil | Feb 21 – Mar 7 | Apr 11 – Apr 25 | — | — |
| Peas | — | — | Feb 21 – Mar 14 | Aug 13 – Sep 3 |
| Spinach | — | — | Feb 21 – Mar 14 | Sep 10 – Oct 1 |
| Radishes | — | — | Feb 28 – Apr 11 | Sep 24 – Oct 15 |
| Cucumbers | Mar 7 – Mar 14 | Apr 18 – Apr 25 | Apr 11 – Apr 25 | Aug 20 – Sep 3 |
| Zucchini & Summer Squash | Mar 7 – Mar 14 | — | Apr 11 – Apr 25 | Aug 27 – Sep 10 |
| Winter Squash & Pumpkins | Mar 7 – Mar 14 | — | Apr 11 – Apr 25 | — |
| Melons & Watermelon | Mar 7 – Mar 14 | Apr 18 – May 2 | — | — |
| Carrots | — | — | Mar 14 – Apr 11 | Aug 13 – Aug 27 |
| Beets | — | — | Mar 14 – Apr 11 | Aug 27 – Sep 10 |
| Potatoes | — | — | Mar 14 – Apr 4 | — |
| Swiss Chard | — | — | Mar 21 – Apr 18 | Aug 27 – Sep 10 |
| Cilantro | — | — | Mar 21 – Apr 11 | Sep 10 – Oct 1 |
| Green Beans | — | — | Apr 11 – May 2 | Aug 20 – Sep 3 |
| Sweet Corn | — | — | Apr 11 – Apr 25 | — |
| Sweet Potatoes | — | Apr 18 – May 9 | — | — |
| Garlic | — | — | — | Oct 22 – Nov 26 |
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 Alton - Melvin Price L&D, IL weather station, 9 km away (elevation 404 ft (123 m)).
ZIP codes in Saint Louis: 63101 63102 63103 63104 63105 63106 63107 63108 63109 63110 63111 63112 63113 63114 63115 63116 63117 63118 63119 63120 63121 63122 63123 63124 63125 63126 63127 63128 63129 63130 63131 63132 63133 63134 63135 63136 63137 63138 63139 63140 63141 63143 63144 63145 63146 63147 63150 63151 63155 63156 63157 63158 63160 63163 63164 63166 63167 63169 63171 63177 …
Frost dates near Saint Louis
- West Alton Apr 4 · Nov 5
- Florissant Apr 2 · Nov 4
- Hazelwood Apr 2 · Nov 4
- Saint Ann Apr 2 · Nov 4
- Bridgeton Apr 2 · Nov 4
- Portage Des Sioux Apr 5 · Oct 27
- Maryland Heights Apr 2 · Nov 4
- Earth City Apr 8 · Oct 29
Frequently asked questions
When is the last frost in Saint Louis, MO?
The median last spring frost in Saint Louis, MO is April 4. There is still about a 10% chance of frost after April 19, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Saint Louis, MO?
The median first fall frost is November 5, with about a 10% chance of frost before October 25.
How long is the growing season in Saint Louis, MO?
About 215 days between the median last spring frost and first fall frost.
What planting zone is Saint Louis, MO?
Saint Louis, MO is in USDA hardiness zone 7a.