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When to plant in Portage, IN

USDA Zone 6a

Everything below — frost dates, hardiness zone, and what to plant when in Portage, Indiana — is derived from the closest NOAA station with complete climate normals.

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

Station · INDIANA DUNES NL · 9.0 km
Last spring frost
April 22
50% chance · 32°F
First fall frost
October 27
50% chance · 32°F
Growing season
188 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 22, first fall frost around October 27, about 188 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

INDIANA DUNES NL · 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 INDIANA DUNES NL.

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 22 and the first fall frost around October 27, giving about 188 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 21May 4Apr 20Oct 4Oct 16Oct 30
32°FMay 8Apr 22Apr 7Oct 15Oct 27Nov 9
28°FApr 23Apr 8Mar 26Oct 26Nov 7Nov 25

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 7July 21
Fall sowin 2 days
Rutabaga
July 21August 4
Fall sowin 16 days
Broccoli
August 4August 18
Fall sowin 16 days
Cabbage
August 4August 18
Fall sowin 16 days
Carrot
August 4August 18
Fall sowin 16 days
Cauliflower
August 4August 18
Fall sowin 16 days
Napa Cabbage
August 4September 1

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 21 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.

INDIANA DUNES NL
Primary
9 km · 207 m elevation
SPRING
Apr 22
FALL
Oct 27
VALPARAISO WTR WKS
15 km · 244 m elevation
SPRING
Apr 22
FALL
Oct 25
VALPARAISO PORTER CO MUNI AP
21 km · 235 m elevation
SPRING
Apr 20
FALL
Oct 26

Portage planting FAQ

When is the last spring frost in Portage, IN?

On average, the last spring frost in Portage is around April 22 (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, IN?

Expect Portage's first fall frost near October 27 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.

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?

There are roughly 188 frost-free days in Portage (a moderate growing season), running from the average last frost around April 22 to the first fall frost near October 27.

When should I plant tomatoes in Portage?

In Portage, 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 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 INDIANA DUNES NL, 9 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, IN — Frost Dates & Zone 6a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00124244. Retrieved from https://blissgarden.com/indiana/portage.
When to Plant in Portage, IN — Frost Dates & Zone 6a — BlissGarden