GreenlySt. Louis: frost dates
United States
In St. Louis the last spring frost usually comes around 6 April and the first autumn frost around 4 November, which leaves about 212 frost-free days (median of 2016–2025). Tomato seedlings can go into open ground around 18 April.
| Last spring frost | around 6 April |
|---|---|
| First autumn frost | around 4 November |
| Frost-free days | 212 days |
Median of 2016–2025 for the 25 km grid cell of the city: the last day at or below 0 °C in spring and the first in autumn (ERA5 reanalysis via Open-Meteo). In a cold year a frost can come a week or two later — Greenly warns 48 hours ahead.
When to sow and plant
| Crop | Sow for seedlings | Plant out in a greenhouse | Open ground |
|---|---|---|---|
| Bell Pepper | 2 February | 17 April | 8 May |
| Chili Pepper | 11 February | 26 April | 17 May |
| Corn | — | 23 March | sow 13 April |
| Cucumber | 6 March | 17 April | 8 May |
| Eggplant | 6 February | 17 April | 8 May |
| Green Beans | 14 February | 23 March | 13 April |
| Melon | 24 February | 17 April | 8 May |
| Peas | — | 23 February | sow 16 March |
| Physalis | 11 February | 28 March | 18 April |
| Pumpkin | 19 February | 28 March | 18 April |
| Sweet Corn | — | 23 March | sow 13 April |
| Tomato | 30 January | 28 March | 18 April |
| Watermelon | 16 March | 17 April | 8 May |
| Zucchini | 24 February | 28 March | 18 April |
Planting out: a week after the last frost once the soil is warm enough for the crop; frost-hardy crops three weeks before it; an unheated greenhouse three weeks earlier. Seedlings are sown so they are ready on that day.
St. Louis: weather for the next 7 days
Forecast by Open-Meteo. Nights at or below 0 °C are marked as frost.
Planted in autumn
| Crop | Plant around |
|---|---|
| Crocus | 5 October |
| Daffodil | 5 October |
| Garlic | 5 October |
| Hyacinth | 5 October |
| Lily | 5 October |
| Tulip | 5 October |
A month before the first autumn frost, so the roots grow before winter.