When to plant in Wentzville, MO
USDA Zone 6bHere are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for Wentzville, Missouri — all computed from Wentzville's nearest NOAA weather station.
Wentzville's nearest full-normals station sits about 21 km out, so treat these as a close estimate — local microclimate can nudge your first and last frost. In zone 6b, Wentzville gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.
Frost probability
WELDON SPRING NWS · 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 Wentzville’s own odds, recorded at WELDON SPRING NWS.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 6 | Apr 22 | Apr 8 | Oct 1 | Oct 16 | Oct 28 |
| 32°F | Apr 26 | Apr 10 | Mar 26 | Oct 12 | Oct 26 | Nov 8 |
| 28°F | Apr 15 | Mar 31 | Mar 12 | Oct 22 | Nov 5 | Nov 22 |
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 Wentzville, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 25 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.
Wentzville planting FAQ
When is the last spring frost in Wentzville, MO?
Wentzville's average last spring frost falls near April 10 — 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 Wentzville, MO?
Expect Wentzville's first fall frost near October 26 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.
What hardiness zone is Wentzville in?
Wentzville is in USDA hardiness zone 6b. In zone 6b, winters are moderate — most common vegetables grow well in season.
How long is the growing season in Wentzville?
Wentzville has about 199 frost-free days — a moderate growing season — between the average last spring frost (April 10) and first fall frost (October 26).
When should I plant tomatoes in Wentzville?
For Wentzville, sow tomatoes indoors about February 13–February 27 and move the seedlings out around April 17, after the last spring frost.
Never miss a window in Wentzville
An email when it’s time to start seeds, transplant, and sow — timed to Wentzville’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Lake St. Louis · 8 km
- O'Fallon · 14 km
- Dardenne Prairie · 16 km
- Troy · 19 km
- St. Peters · 23 km
- St. Charles · 31 km
- Chesterfield · 31 km
- Wildwood · 32 km
Frost dates recorded at WELDON SPRING NWS, 21 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 Wentzville, MO — Frost Dates & Zone 6b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00238805. Retrieved from https://blissgarden.com/missouri/wentzville.