blissgarden.

When to plant in Oak Creek, WI

USDA Zone 6a

Here are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for Oak Creek, Wisconsin — all computed from Oak Creek's nearest NOAA weather station.

Zone 6a means Oak Creek sees real winter cold, but a good range of perennials survive; the frost dates above govern when annual vegetables go out.

Station · SOUTH MILWAUKEE WWTP · 4.7 km
Last spring frost
April 22
50% chance · 32°F
First fall frost
October 26
50% chance · 32°F
Growing season
187 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for Oak CreekA year-band showing 32°F frost risk from January to December for Oak Creek: last spring frost around April 22, first fall frost around October 26, about 187 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

SOUTH MILWAUKEE WWTP · 1991–2020

The 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 Oak Creek’s own odds, recorded at SOUTH MILWAUKEE WWTP.

Frost-probability curves for Oak CreekProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around April 22 and the first fall frost around October 26, giving about 187 frost-free days.
Last spring frostFirst fall frostbold = 32°F · thin = 28°F / 36°F · dot = 50% date · band = 10–90% window
ThresholdSPRING 10%SPRING 50%SPRING 90%FALL 10%FALL 50%FALL 90%
36°FMay 24May 5Apr 21Oct 1Oct 16Oct 28
32°FMay 8Apr 22Apr 9Oct 10Oct 26Nov 8
28°FApr 24Apr 9Mar 28Oct 24Nov 5Nov 20

Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.

What to plant now

TODAY · JULY 19
Fall sowopen now
Brussels Sprouts
July 6July 20
Fall sowin 1 days
Rutabaga
July 20August 3
Fall sowin 15 days
Broccoli
August 3August 17
Fall sowin 15 days
Cabbage
August 3August 17
Fall sowin 15 days
Carrot
August 3August 17
Fall sowin 15 days
Cauliflower
August 3August 17
Fall sowin 15 days
Napa Cabbage
August 3August 31

Add these crops to your calendar (.ics) ↓

Full-year planting calendar

Start indoorsTransplantDirect sowFall sow

Each bar is the exact window to take a planting action in Oak Creek, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 13 km · complete 32°F normals

When 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 WWTP
Primary
5 km · 198 m elevation
SPRING
Apr 22
FALL
Oct 26
MILWAUKEE MITCHELL AP
8 km · 204 m elevation
SPRING
Apr 19
FALL
Oct 29
HALES CORNERS/WHITNALL PARK/BO
13 km · 236 m elevation
SPRING
May 3
FALL
Oct 14

Oak Creek planting FAQ

When is the last spring frost in Oak Creek, WI?

Plan for the last spring frost in Oak Creek 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 Oak Creek, WI?

Expect Oak Creek'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 Oak Creek in?

Oak Creek 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 Oak Creek?

There are roughly 187 frost-free days in Oak Creek (a moderate growing season), running from the average last frost around April 22 to the first fall frost near October 26.

When should I plant tomatoes in Oak Creek?

In Oak Creek, start tomato seeds indoors around February 25–March 11, then transplant seedlings outdoors around April 29 once the danger of frost has passed.

Planting reminders

Never miss a window in Oak Creek

An email when it’s time to start seeds, transplant, and sow — timed to Oak Creek’s frost dates. Double opt-in, one-click unsubscribe, no spam.

Nearby cities

8 within reach

Frost dates recorded at SOUTH MILWAUKEE WWTP, 5 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.

Cite this page
BlissGarden. "When to Plant in Oak Creek, WI — Frost Dates & Zone 6a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00477964. Retrieved from https://blissgarden.com/wisconsin/oak-creek.
When to Plant in Oak Creek, WI — Frost Dates & Zone 6a — BlissGarden