When to plant in St. Joseph, MO
USDA Zone 6aEverything below — frost dates, hardiness zone, and what to plant when in St. Joseph, Missouri — is derived from the closest NOAA station with complete climate normals.
Zone 6a means St. Joseph sees real winter cold, but a good range of perennials survive; the frost dates above govern when annual vegetables go out.
Frost probability
ST JOSEPH ROSECRANS 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. Joseph’s own odds, recorded at ST JOSEPH ROSECRANS AP.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 9 | Apr 29 | Apr 15 | Sep 21 | Oct 5 | Oct 20 |
| 32°F | May 3 | Apr 19 | Apr 5 | Sep 30 | Oct 17 | Oct 30 |
| 28°F | Apr 24 | Apr 9 | Mar 25 | Oct 13 | Oct 26 | Nov 8 |
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. Joseph, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 24 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. Joseph planting FAQ
When is the last spring frost in St. Joseph, MO?
Plan for the last spring frost in St. Joseph around April 19 (the date it has a 50% chance of a 32°F freeze). Anything frost-sensitive should go out after it.
When is the first fall frost in St. Joseph, MO?
In St. Joseph, the first 32°F freeze of fall lands around October 17 on average. Time your last harvests and any season-extension cover before it.
What hardiness zone is St. Joseph in?
St. Joseph is in USDA hardiness zone 6a. In zone 6a, winters are moderate — most common vegetables grow well in season.
How long is the growing season in St. Joseph?
There are roughly 181 frost-free days in St. Joseph (a moderate growing season), running from the average last frost around April 19 to the first fall frost near October 17.
When should I plant tomatoes in St. Joseph?
In St. Joseph, start tomato seeds indoors around February 22–March 8, then transplant seedlings outdoors around April 26 once the danger of frost has passed.
Never miss a window in St. Joseph
An email when it’s time to start seeds, transplant, and sow — timed to St. Joseph’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Atchison · 35 km
- Smithville · 46 km
- Leavenworth · 49 km
- Lansing · 58 km
- Kearney · 60 km
- Gladstone · 65 km
- Maryville · 65 km
- Liberty · 67 km
Frost dates recorded at ST JOSEPH ROSECRANS AP, 9 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. Joseph, MO — Frost Dates & Zone 6a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00013993. Retrieved from https://blissgarden.com/missouri/st-joseph.