Frost dates for 63128 — Saint Louis, MO
How Saint Louis compares
- In 8 years out of 10, the last spring frost in Saint Louis falls between March 22 and April 20, a 29-day window. The first fall frost falls between October 14 and November 7.
- The median last frost is 6 days earlier than the Missouri median of Apr 12.
- Its 204-day growing season is longer than 77% of the 938 Missouri places with a regular frost season (state median 195 days).
- The last frost is 10 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 97 nights a year at or below 32°F.
- Compared with Florissant, MO, 31 km away, the last frost here is 4 days later than there and the growing season is 12 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | March 22 |
| 50% (median) | April 6 |
| 10% (safe for tender plants) | April 20 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 14 |
| 50% (median) | October 27 |
| 90% (late) | November 7 |
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 63128 — Saint Louis, MO — last frost Apr 6, first frost Oct 27, zone 7a. whenisthelastfrost.com
When to plant vegetables in Saint Louis, MO
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 12 – Jan 26 | Mar 9 – Mar 23 | — | — |
| Peppers | Jan 26 – Feb 9 | Apr 20 – May 4 | — | — |
| Eggplant | Jan 26 – Feb 9 | Apr 20 – May 4 | — | — |
| Tomatoes | Feb 9 – Feb 23 | Apr 13 – Apr 27 | — | — |
| Lettuce | Feb 9 – Feb 23 | Mar 16 – Mar 30 | Mar 9 – Apr 13 | Sep 1 – Sep 29 |
| Kale | Feb 9 – Feb 23 | Mar 9 – Mar 23 | Mar 9 – Mar 23 | Aug 18 – Sep 8 |
| Broccoli | Feb 9 – Feb 23 | Mar 23 – Apr 6 | — | Jul 21 – Aug 11 |
| Cabbage | Feb 9 – Feb 23 | Mar 16 – Mar 30 | — | Jul 21 – Aug 11 |
| Cauliflower | Feb 9 – Feb 23 | Mar 23 – Apr 6 | — | Jul 21 – Aug 11 |
| Okra | Feb 23 – Mar 9 | Apr 27 – May 11 | Apr 27 – May 11 | — |
| Basil | Feb 23 – Mar 9 | Apr 13 – Apr 27 | — | — |
| Peas | — | — | Feb 23 – Mar 16 | Aug 4 – Aug 25 |
| Spinach | — | — | Feb 23 – Mar 16 | Sep 1 – Sep 22 |
| Radishes | — | — | Mar 2 – Apr 13 | Sep 15 – Oct 6 |
| Cucumbers | Mar 9 – Mar 16 | Apr 20 – Apr 27 | Apr 13 – Apr 27 | Aug 11 – Aug 25 |
| Zucchini & Summer Squash | Mar 9 – Mar 16 | — | Apr 13 – Apr 27 | Aug 18 – Sep 1 |
| Winter Squash & Pumpkins | Mar 9 – Mar 16 | — | Apr 13 – Apr 27 | — |
| Melons & Watermelon | Mar 9 – Mar 16 | Apr 20 – May 4 | — | — |
| Carrots | — | — | Mar 16 – Apr 13 | Aug 4 – Aug 18 |
| Beets | — | — | Mar 16 – Apr 13 | Aug 18 – Sep 1 |
| Potatoes | — | — | Mar 16 – Apr 6 | — |
| Swiss Chard | — | — | Mar 23 – Apr 20 | Aug 18 – Sep 1 |
| Cilantro | — | — | Mar 23 – Apr 13 | Sep 1 – Sep 22 |
| Green Beans | — | — | Apr 13 – May 4 | Aug 11 – Aug 25 |
| Sweet Corn | — | — | Apr 13 – Apr 27 | — |
| Sweet Potatoes | — | Apr 20 – May 11 | — | — |
| Garlic | — | — | — | Oct 13 – Nov 17 |
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 Cahokia, IL weather station, 18 km away (elevation 400 ft (122 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
- Arnold Apr 9 · Oct 26
- Fenton Apr 4 · Oct 29
- Imperial Apr 9 · Oct 26
- Valley Park Apr 4 · Oct 29
- High Ridge Apr 12 · Oct 23
- Kimmswick Apr 9 · Oct 26
- Liguori Apr 9 · Oct 26
- Barnhart Apr 9 · Oct 26
Frequently asked questions
When is the last frost in Saint Louis, MO?
The median last spring frost in Saint Louis, MO is April 6. There is still about a 10% chance of frost after April 20, 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 October 27, with about a 10% chance of frost before October 14.
How long is the growing season in Saint Louis, MO?
About 204 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.