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When to plant in Portage, MI

USDA Zone 6a

Portage, Michigan frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.

In zone 6a, Portage gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.

Station · KALAMAZOO BATTLE CK INTL AP · 5.3 km
Last spring frost
April 28
50% chance · 32°F
First fall frost
October 18
50% chance · 32°F
Growing season
173 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for PortageA year-band showing 32°F frost risk from January to December for Portage: last spring frost around April 28, first fall frost around October 18, about 173 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

KALAMAZOO BATTLE CK INTL AP · 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 Portage’s own odds, recorded at KALAMAZOO BATTLE CK INTL AP.

Frost-probability curves for PortageProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around April 28 and the first fall frost around October 18, giving about 173 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 8Apr 24Sep 22Oct 6Oct 19
32°FMay 13Apr 28Apr 13Oct 2Oct 18Nov 1
28°FMay 3Apr 17Apr 3Oct 16Nov 1Nov 14

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
Rutabaga
July 12July 26
Fall sowin 7 days
Broccoli
July 26August 9
Fall sowin 7 days
Cabbage
July 26August 9
Fall sowin 7 days
Carrot
July 26August 9
Fall sowin 7 days
Cauliflower
July 26August 9
Fall sowin 7 days
Napa Cabbage
July 26August 23
Fall sowin 21 days
Beet
August 9August 23
Fall sowin 21 days
Collards
August 9September 6
Fall sowin 21 days
Endive
August 9August 23
Fall sowin 21 days
Escarole
August 9August 23
Fall sowin 21 days
Fennel (Bulb)
August 9August 23
Fall sowin 21 days
Kale
August 9September 6
Fall sowin 21 days
Kohlrabi
August 9September 6
Fall sowin 21 days
Peas
August 9August 23
Fall sowin 21 days
Radicchio
August 9August 23
Fall sowin 21 days
Swiss Chard
August 9August 23
Fall sowin 21 days
Turnip
August 9September 6

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 Portage, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 30 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.

KALAMAZOO BATTLE CK INTL AP
Primary
5 km · 265 m elevation
SPRING
Apr 28
FALL
Oct 18
GULL LAKE BIOLOGICAL STN
28 km · 282 m elevation
SPRING
Apr 29
FALL
Oct 20
THREE RIVERS
30 km · 247 m elevation
SPRING
Apr 30
FALL
Oct 17

Portage planting FAQ

When is the last spring frost in Portage, MI?

On average, the last spring frost in Portage is around April 28 (50% probability at 32°F, from 1991–2020 NOAA normals). Wait until after this date to set out tender plants like tomatoes and peppers.

When is the first fall frost in Portage, MI?

The first fall frost in Portage typically arrives around October 18 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.

What hardiness zone is Portage in?

Portage 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 Portage?

Portage has about 173 frost-free days — a moderate growing season — between the average last spring frost (April 28) and first fall frost (October 18).

When should I plant tomatoes in Portage?

For Portage, sow tomatoes indoors about March 3–March 17 and move the seedlings out around May 5, after the last spring frost.

Planting reminders

Never miss a window in Portage

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

Nearby cities

8 within reach

Frost dates recorded at KALAMAZOO BATTLE CK INTL AP, 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 Portage, MI — Frost Dates & Zone 6a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00094815. Retrieved from https://blissgarden.com/michigan/portage.
When to Plant in Portage, MI — Frost Dates & Zone 6a — BlissGarden