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When to plant in Northfield, MN

USDA Zone 4b

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

Northfield's nearest full-normals station sits about 18 km out, so treat these as a close estimate — local microclimate can nudge your first and last frost. In zone 4b, Northfield winters are severe; choose cold-hardy perennials and time annuals carefully around the frost dates above.

Station · FARIBAULT · 18.0 km
Last spring frost
May 5
50% chance · 32°F
First fall frost
October 5
50% chance · 32°F
Growing season
153 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for NorthfieldA year-band showing 32°F frost risk from January to December for Northfield: last spring frost around May 5, first fall frost around October 5, about 153 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

The average first fall frost in Northfield is now 6 days later than in the 1981–2010 normals. See how frost dates are shifting nationwide →

Frost probability

FARIBAULT · 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 Northfield’s own odds, recorded at FARIBAULT.

Frost-probability curves for NorthfieldProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around May 5 and the first fall frost around October 5, giving about 153 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 29May 15May 1Sep 12Sep 27Oct 9
32°FMay 19May 5Apr 22Sep 21Oct 5Oct 17
28°FMay 10Apr 26Apr 11Oct 1Oct 13Oct 27

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
Broccoli
July 13July 27
Fall sowopen now
Cabbage
July 13July 27
Fall sowopen now
Carrot
July 13July 27
Fall sowopen now
Cauliflower
July 13July 27
Fall sowopen now
Napa Cabbage
July 13August 10
Fall sowin 8 days
Beet
July 27August 10
Fall sowin 8 days
Collards
July 27August 24
Fall sowin 8 days
Endive
July 27August 10
Fall sowin 8 days
Escarole
July 27August 10
Fall sowin 8 days
Fennel (Bulb)
July 27August 10
Fall sowin 8 days
Kale
July 27August 24
Fall sowin 8 days
Kohlrabi
July 27August 24
Fall sowin 8 days
Peas
July 27August 10
Fall sowin 8 days
Radicchio
July 27August 10
Fall sowin 8 days
Swiss Chard
July 27August 10
Fall sowin 8 days
Turnip
July 27August 24
Fall sowin 22 days
Arugula
August 10September 7
Fall sowin 22 days
Bok Choy
August 10August 24
Fall sowin 22 days
Chervil
August 10September 7
Fall sowin 22 days
Cilantro
August 10September 7
Fall sowin 22 days
Claytonia (Miner's Lettuce)
August 10September 7
Fall sowin 22 days
Corn Salad (Mâche)
August 10September 7
Fall sowin 22 days
Gai Lan (Chinese Broccoli)
August 10August 24
Fall sowin 22 days
Lettuce
August 10September 7
Fall sowin 22 days
Mizuna
August 10September 7
Fall sowin 22 days
Mustard Greens
August 10September 7
Fall sowin 22 days
Radish
August 10September 7
Fall sowin 22 days
Shungiku (Edible Chrysanthemum)
August 10August 24
Fall sowin 22 days
Spinach
August 10September 7
Fall sowin 22 days
Tatsoi
August 10September 7

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 Northfield, 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.

FARIBAULT
Primary
18 km · 296 m elevation
SPRING
May 5
FALL
Oct 5
FARMINGTON 3 NW
24 km · 299 m elevation
SPRING
Apr 27
FALL
Oct 10
ROSEMOUNT RSCH & OUTREACH CTR
30 km · 288 m elevation
SPRING
May 2
FALL
Oct 5

Northfield planting FAQ

When is the last spring frost in Northfield, MN?

Plan for the last spring frost in Northfield around May 5 (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 Northfield, MN?

Expect Northfield's first fall frost near October 5 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.

What hardiness zone is Northfield in?

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

How long is the growing season in Northfield?

Northfield has about 153 frost-free days — a moderate growing season — between the average last spring frost (May 5) and first fall frost (October 5).

When should I plant tomatoes in Northfield?

For Northfield, sow tomatoes indoors about March 10–March 24 and move the seedlings out around May 12, after the last spring frost.

Planting reminders

Never miss a window in Northfield

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

Nearby cities

8 within reach

Frost dates recorded at FARIBAULT, 18 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 Northfield, MN — Frost Dates & Zone 4b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00212721. Retrieved from https://blissgarden.com/minnesota/northfield.
When to Plant in Northfield, MN — Frost Dates & Zone 4b — BlissGarden