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When to plant in Grand Rapids, MN

USDA Zone 4a

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

In zone 4a, Grand Rapids winters are severe; choose cold-hardy perennials and time annuals carefully around the frost dates above.

Station · GRAND RPDS FOREST LAB · 2.7 km
Last spring frost
May 17
50% chance · 32°F
First fall frost
September 24
50% chance · 32°F
Growing season
130 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for Grand RapidsA year-band showing 32°F frost risk from January to December for Grand Rapids: last spring frost around May 17, first fall frost around September 24, about 130 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

GRAND RPDS FOREST LAB · 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 Grand Rapids’s own odds, recorded at GRAND RPDS FOREST LAB.

Frost-probability curves for Grand RapidsProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around May 17 and the first fall frost around September 24, giving about 130 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°FJun 13May 29May 16Aug 30Sep 15Sep 27
32°FMay 31May 17May 3Sep 10Sep 24Oct 7
28°FMay 19May 6Apr 24Sep 20Oct 5Oct 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
Napa Cabbage
July 2July 30
Fall sowopen now
Beet
July 16July 30
Fall sowopen now
Collards
July 16August 13
Fall sowopen now
Endive
July 16July 30
Fall sowopen now
Escarole
July 16July 30
Fall sowopen now
Fennel (Bulb)
July 16July 30
Fall sowopen now
Kale
July 16August 13
Fall sowopen now
Kohlrabi
July 16August 13
Fall sowopen now
Peas
July 16July 30
Fall sowopen now
Radicchio
July 16July 30
Fall sowopen now
Swiss Chard
July 16July 30
Fall sowopen now
Turnip
July 16August 13
Fall sowin 11 days
Arugula
July 30August 27
Fall sowin 11 days
Bok Choy
July 30August 13
Fall sowin 11 days
Chervil
July 30August 27
Fall sowin 11 days
Cilantro
July 30August 27
Fall sowin 11 days
Claytonia (Miner's Lettuce)
July 30August 27
Fall sowin 11 days
Corn Salad (Mâche)
July 30August 27
Fall sowin 11 days
Gai Lan (Chinese Broccoli)
July 30August 13
Fall sowin 11 days
Lettuce
July 30August 27
Fall sowin 11 days
Mizuna
July 30August 27
Fall sowin 11 days
Mustard Greens
July 30August 27
Fall sowin 11 days
Radish
July 30August 27
Fall sowin 11 days
Shungiku (Edible Chrysanthemum)
July 30August 13
Fall sowin 11 days
Spinach
July 30August 27
Fall sowin 11 days
Tatsoi
July 30August 27

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

Nearby weather stations

3 within 45 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.

GRAND RPDS FOREST LAB
Primary
3 km · 399 m elevation
SPRING
May 17
FALL
Sep 24
POKEGAMA DAM
4 km · 390 m elevation
SPRING
May 16
FALL
Oct 1
MARCELL 5NE
45 km · 423 m elevation
SPRING
May 14
FALL
Oct 2

Grand Rapids planting FAQ

When is the last spring frost in Grand Rapids, MN?

On average, the last spring frost in Grand Rapids is around May 17 (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 Grand Rapids, MN?

Expect Grand Rapids's first fall frost near September 24 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.

What hardiness zone is Grand Rapids in?

Grand Rapids is in USDA hardiness zone 4a. In zone 4a, winters are cold — pick cold-hardy varieties and protect tender crops.

How long is the growing season in Grand Rapids?

Grand Rapids has about 130 frost-free days — a short growing season — between the average last spring frost (May 17) and first fall frost (September 24).

When should I plant tomatoes in Grand Rapids?

For Grand Rapids, sow tomatoes indoors about March 22–April 5 and move the seedlings out around May 24, after the last spring frost.

Planting reminders

Never miss a window in Grand Rapids

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

Nearby cities

8 within reach

Frost dates recorded at GRAND RPDS FOREST LAB, 3 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 Grand Rapids, MN — Frost Dates & Zone 4a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00213303. Retrieved from https://blissgarden.com/minnesota/grand-rapids.
When to Plant in Grand Rapids, MN — Frost Dates & Zone 4a — BlissGarden