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When to plant in La Grande, OR

USDA Zone 6b

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

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

Station · LA GRANDE · 1.3 km
Last spring frost
May 6
50% chance · 32°F
First fall frost
October 1
50% chance · 32°F
Growing season
148 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for La GrandeA year-band showing 32°F frost risk from January to December for La Grande: last spring frost around May 6, first fall frost around October 1, about 148 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

LA GRANDE · 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 La Grande’s own odds, recorded at LA GRANDE.

Frost-probability curves for La GrandeProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around May 6 and the first fall frost around October 1, giving about 148 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 14May 26May 7Sep 3Sep 19Oct 3
32°FMay 26May 6Apr 21Sep 17Oct 1Oct 16
28°FMay 5Apr 19Apr 1Sep 30Oct 14Oct 29

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 9July 23
Fall sowopen now
Cabbage
July 9July 23
Fall sowopen now
Carrot
July 9July 23
Fall sowopen now
Cauliflower
July 9July 23
Fall sowopen now
Napa Cabbage
July 9August 6
Fall sowin 4 days
Beet
July 23August 6
Fall sowin 4 days
Collards
July 23August 20
Fall sowin 4 days
Endive
July 23August 6
Fall sowin 4 days
Escarole
July 23August 6
Fall sowin 4 days
Fennel (Bulb)
July 23August 6
Fall sowin 4 days
Kale
July 23August 20
Fall sowin 4 days
Kohlrabi
July 23August 20
Fall sowin 4 days
Peas
July 23August 6
Fall sowin 4 days
Radicchio
July 23August 6
Fall sowin 4 days
Swiss Chard
July 23August 6
Fall sowin 4 days
Turnip
July 23August 20
Fall sowin 18 days
Arugula
August 6September 3
Fall sowin 18 days
Bok Choy
August 6August 20
Fall sowin 18 days
Chervil
August 6September 3
Fall sowin 18 days
Cilantro
August 6September 3
Fall sowin 18 days
Claytonia (Miner's Lettuce)
August 6September 3
Fall sowin 18 days
Corn Salad (Mâche)
August 6September 3
Fall sowin 18 days
Gai Lan (Chinese Broccoli)
August 6August 20
Fall sowin 18 days
Lettuce
August 6September 3
Fall sowin 18 days
Mizuna
August 6September 3
Fall sowin 18 days
Mustard Greens
August 6September 3
Fall sowin 18 days
Radish
August 6September 3
Fall sowin 18 days
Shungiku (Edible Chrysanthemum)
August 6August 20
Fall sowin 18 days
Spinach
August 6September 3
Fall sowin 18 days
Tatsoi
August 6September 3

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 La Grande, 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.

LA GRANDE
Primary
1 km · 840 m elevation
SPRING
May 6
FALL
Oct 1
UNION
22 km · 846 m elevation
SPRING
May 11
FALL
Sep 26
ELGIN
30 km · 822 m elevation
SPRING
May 24
FALL
Sep 18

La Grande planting FAQ

When is the last spring frost in La Grande, OR?

On average, the last spring frost in La Grande is around May 6 (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 La Grande, OR?

Expect La Grande's first fall frost near October 1 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.

What hardiness zone is La Grande in?

La Grande is in USDA hardiness zone 6b. In zone 6b, winters are moderate — most common vegetables grow well in season.

How long is the growing season in La Grande?

There are roughly 148 frost-free days in La Grande (a short growing season), running from the average last frost around May 6 to the first fall frost near October 1.

When should I plant tomatoes in La Grande?

In La Grande, start tomato seeds indoors around March 11–March 25, then transplant seedlings outdoors around May 13 once the danger of frost has passed.

Planting reminders

Never miss a window in La Grande

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

Nearby cities

8 within reach

Frost dates recorded at LA GRANDE, 1 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 La Grande, OR — Frost Dates & Zone 6b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00354622. Retrieved from https://blissgarden.com/oregon/la-grande.
When to Plant in La Grande, OR — Frost Dates & Zone 6b — BlissGarden