When to plant in New Berlin, WI
USDA Zone 5bEverything below — frost dates, hardiness zone, and what to plant when in New Berlin, Wisconsin — is derived from the closest NOAA station with complete climate normals.
In zone 5b, New Berlin gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.
Frost probability
HALES CORNERS/WHITNALL PARK/BO · 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 New Berlin’s own odds, recorded at HALES CORNERS/WHITNALL PARK/BO.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 29 | May 14 | Apr 30 | Sep 22 | Oct 3 | Oct 15 |
| 32°F | May 19 | May 3 | Apr 18 | Sep 30 | Oct 14 | Oct 26 |
| 28°F | May 9 | Apr 21 | Apr 8 | Oct 8 | Oct 24 | Nov 6 |
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 New Berlin, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 10 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.
New Berlin planting FAQ
When is the last spring frost in New Berlin, WI?
New Berlin's average last spring frost falls near May 3 — 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 New Berlin, WI?
In New Berlin, the first 32°F freeze of fall lands around October 14 on average. Time your last harvests and any season-extension cover before it.
What hardiness zone is New Berlin in?
New Berlin 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 New Berlin?
New Berlin has about 164 frost-free days — a moderate growing season — between the average last spring frost (May 3) and first fall frost (October 14).
When should I plant tomatoes in New Berlin?
For New Berlin, sow tomatoes indoors about March 8–March 22 and move the seedlings out around May 10, after the last spring frost.
Never miss a window in New Berlin
An email when it’s time to start seeds, transplant, and sow — timed to New Berlin’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- West Allis · 9 km
- Greenfield · 10 km
- Waukesha · 10 km
- Brookfield · 10 km
- Greendale · 11 km
- Muskego · 11 km
- Wauwatosa · 13 km
- Franklin · 14 km
Frost dates recorded at HALES CORNERS/WHITNALL PARK/BO, 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 New Berlin, WI — Frost Dates & Zone 5b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00473391. Retrieved from https://blissgarden.com/wisconsin/new-berlin.