When to plant in South Milwaukee, WI
USDA Zone 6aHere are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for South Milwaukee, Wisconsin — all computed from South Milwaukee's nearest NOAA weather station.
In zone 6a, South Milwaukee gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.
Frost probability
SOUTH MILWAUKEE 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 South Milwaukee’s own odds, recorded at SOUTH MILWAUKEE WWTP.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 24 | May 5 | Apr 21 | Oct 1 | Oct 16 | Oct 28 |
| 32°F | May 8 | Apr 22 | Apr 9 | Oct 10 | Oct 26 | Nov 8 |
| 28°F | Apr 24 | Apr 9 | Mar 28 | Oct 24 | Nov 5 | Nov 20 |
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 South Milwaukee, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 14 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.
South Milwaukee planting FAQ
When is the last spring frost in South Milwaukee, WI?
Plan for the last spring frost in South Milwaukee around April 22 (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 South Milwaukee, WI?
Expect South Milwaukee'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 South Milwaukee in?
South Milwaukee 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 South Milwaukee?
South Milwaukee has about 187 frost-free days — a moderate growing season — between the average last spring frost (April 22) and first fall frost (October 26).
When should I plant tomatoes in South Milwaukee?
For South Milwaukee, sow tomatoes indoors about February 25–March 11 and move the seedlings out around April 29, after the last spring frost.
Never miss a window in South Milwaukee
An email when it’s time to start seeds, transplant, and sow — timed to South Milwaukee’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Cudahy · 4 km
- Oak Creek · 5 km
- Greendale · 12 km
- Franklin · 13 km
- Greenfield · 13 km
- Caledonia · 13 km
- West Allis · 17 km
- Milwaukee · 19 km
Frost dates recorded at SOUTH MILWAUKEE WWTP, 2 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 South Milwaukee, WI — Frost Dates & Zone 6a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00477964. Retrieved from https://blissgarden.com/wisconsin/south-milwaukee.