When to plant in Des Moines, IA
USDA Zone 5bEverything below — frost dates, hardiness zone, and what to plant when in Des Moines, Iowa — is derived from the closest NOAA station with complete climate normals.
Zone 5b means Des Moines sees real winter cold, but a good range of perennials survive; the frost dates above govern when annual vegetables go out.
Frost probability
DES MOINES 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 Des Moines’s own odds, recorded at DES MOINES INTL AP.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 10 | Apr 29 | Apr 15 | Sep 25 | Oct 9 | Oct 22 |
| 32°F | May 2 | Apr 18 | Apr 4 | Oct 4 | Oct 20 | Nov 1 |
| 28°F | Apr 22 | Apr 8 | Mar 25 | Oct 16 | Oct 30 | Nov 11 |
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 Des Moines, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 21 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.
Des Moines planting FAQ
When is the last spring frost in Des Moines, IA?
Plan for the last spring frost in Des Moines around April 18 (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 Des Moines, IA?
In Des Moines, the first 32°F freeze of fall lands around October 20 on average. Time your last harvests and any season-extension cover before it.
What hardiness zone is Des Moines in?
Des Moines is in USDA hardiness zone 5b. In zone 5b, winters are cold — pick cold-hardy varieties and protect tender crops.
How long is the growing season in Des Moines?
There are roughly 185 frost-free days in Des Moines (a moderate growing season), running from the average last frost around April 18 to the first fall frost near October 20.
When should I plant tomatoes in Des Moines?
In Des Moines, start tomato seeds indoors around February 21–March 7, then transplant seedlings outdoors around April 25 once the danger of frost has passed.
Never miss a window in Des Moines
An email when it’s time to start seeds, transplant, and sow — timed to Des Moines’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Pleasant Hill · 9 km
- Norwalk · 12 km
- Altoona · 14 km
- West Des Moines · 14 km
- Urbandale · 16 km
- Johnston · 16 km
- Clive · 16 km
- Ankeny · 18 km
Frost dates recorded at DES MOINES INTL AP, 6 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 Des Moines, IA — Frost Dates & Zone 5b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00014933. Retrieved from https://blissgarden.com/iowa/des-moines.