When to plant in St. Ann, MO
USDA Zone 7aHere are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for St. Ann, Missouri — all computed from St. Ann's nearest NOAA weather station.
In zone 7a, St. Ann supports a wide range of perennials year-round; the frost dates above are what set your annual vegetable timing.
Frost probability
ST LOUIS LAMBERT INTL AP · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are St. Ann’s own odds, recorded at ST LOUIS LAMBERT INTL AP.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | Apr 28 | Apr 13 | Mar 31 | Oct 14 | Oct 26 | Nov 6 |
| 32°F | Apr 17 | Apr 2 | Mar 17 | Oct 23 | Nov 4 | Nov 18 |
| 28°F | Apr 7 | Mar 23 | Mar 5 | Nov 2 | Nov 13 | Nov 30 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in St. Ann, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 15 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
St. Ann planting FAQ
When is the last spring frost in St. Ann, MO?
St. Ann's average last spring frost falls near April 2 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.
When is the first fall frost in St. Ann, MO?
The first fall frost in St. Ann typically arrives around November 4 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is St. Ann in?
St. Ann is in USDA hardiness zone 7a. In zone 7a, winters are moderate — most common vegetables grow well in season.
How long is the growing season in St. Ann?
St. Ann has about 216 frost-free days — a long growing season — between the average last spring frost (April 2) and first fall frost (November 4).
When should I plant tomatoes in St. Ann?
For St. Ann, sow tomatoes indoors about February 5–February 19 and move the seedlings out around April 9, after the last spring frost.
Never miss a window in St. Ann
An email when it’s time to start seeds, transplant, and sow — timed to St. Ann’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Overland · 4 km
- Bridgeton · 6 km
- Maryland Heights · 7 km
- Hazelwood · 8 km
- Ferguson · 8 km
- University City · 8 km
- Creve Coeur · 9 km
- Florissant · 10 km
Frost dates recorded at ST LOUIS LAMBERT INTL AP, 3 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in St. Ann, MO — Frost Dates & Zone 7a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00013994. Retrieved from https://blissgarden.com/missouri/st-ann.