When to plant in Cedarburg, WI
USDA Zone 5bHere are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for Cedarburg, Wisconsin — all computed from Cedarburg's nearest NOAA weather station.
Zone 5b means Cedarburg sees real winter cold, but a good range of perennials survive; the frost dates above govern when annual vegetables go out.
Frost probability
GRAFTON WWTP · 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 Cedarburg’s own odds, recorded at GRAFTON WWTP.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 23 | May 5 | Apr 20 | Sep 27 | Oct 11 | Oct 26 |
| 32°F | May 9 | Apr 23 | Apr 10 | Oct 8 | Oct 24 | Nov 5 |
| 28°F | Apr 24 | Apr 11 | Mar 31 | Oct 21 | Nov 2 | Nov 15 |
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 Cedarburg, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 11 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.
Cedarburg planting FAQ
When is the last spring frost in Cedarburg, WI?
Cedarburg's average last spring frost falls near April 23 — 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 Cedarburg, WI?
The first fall frost in Cedarburg typically arrives around October 24 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Cedarburg in?
Cedarburg 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 Cedarburg?
There are roughly 184 frost-free days in Cedarburg (a moderate growing season), running from the average last frost around April 23 to the first fall frost near October 24.
When should I plant tomatoes in Cedarburg?
In Cedarburg, start tomato seeds indoors around February 26–March 12, then transplant seedlings outdoors around April 30 once the danger of frost has passed.
Never miss a window in Cedarburg
An email when it’s time to start seeds, transplant, and sow — timed to Cedarburg’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Grafton · 4 km
- Mequon · 10 km
- Port Washington · 13 km
- Germantown · 13 km
- Brown Deer · 14 km
- Menomonee Falls · 19 km
- Glendale · 20 km
- West Bend · 20 km
Frost dates recorded at GRAFTON WWTP, 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 Cedarburg, WI — Frost Dates & Zone 5b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00473198. Retrieved from https://blissgarden.com/wisconsin/cedarburg.