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When to plant in Nampa, ID

USDA Zone 7a

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

In zone 7a, Nampa supports a wide range of perennials year-round; the frost dates above are what set your annual vegetable timing.

Station · NAMPA SUGAR FACTORY · 2.1 km
Last spring frost
April 29
50% chance · 32°F
First fall frost
October 13
50% chance · 32°F
Growing season
167 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for NampaA year-band showing 32°F frost risk from January to December for Nampa: last spring frost around April 29, first fall frost around October 13, about 167 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

The average first fall frost in Nampa is now 5 days later than in the 1981–2010 normals. See how frost dates are shifting nationwide →

Frost probability

NAMPA SUGAR FACTORY · 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 Nampa’s own odds, recorded at NAMPA SUGAR FACTORY.

Frost-probability curves for NampaProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around April 29 and the first fall frost around October 13, giving about 167 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 6May 16May 1Sep 15Sep 30Oct 14
32°FMay 18Apr 29Apr 15Sep 29Oct 13Oct 28
28°FMay 1Apr 11Mar 25Oct 9Oct 25Nov 10

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 7July 21
Fall sowin 2 days
Broccoli
July 21August 4
Fall sowin 2 days
Cabbage
July 21August 4
Fall sowin 2 days
Carrot
July 21August 4
Fall sowin 2 days
Cauliflower
July 21August 4
Fall sowin 2 days
Napa Cabbage
July 21August 18
Fall sowin 16 days
Beet
August 4August 18
Fall sowin 16 days
Collards
August 4September 1
Fall sowin 16 days
Endive
August 4August 18
Fall sowin 16 days
Escarole
August 4August 18
Fall sowin 16 days
Fennel (Bulb)
August 4August 18
Fall sowin 16 days
Kale
August 4September 1
Fall sowin 16 days
Kohlrabi
August 4September 1
Fall sowin 16 days
Peas
August 4August 18
Fall sowin 16 days
Radicchio
August 4August 18
Fall sowin 16 days
Swiss Chard
August 4August 18
Fall sowin 16 days
Turnip
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 Nampa, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 26 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.

NAMPA SUGAR FACTORY
Primary
2 km · 753 m elevation
SPRING
Apr 29
FALL
Oct 13
DEER FLAT DAM
15 km · 765 m elevation
SPRING
Apr 23
FALL
Oct 18
BOISE AIR TERMINAL
26 km · 858 m elevation
SPRING
Apr 24
FALL
Oct 21

Nampa planting FAQ

When is the last spring frost in Nampa, ID?

Nampa's average last spring frost falls near April 29 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.

When is the first fall frost in Nampa, ID?

The first fall frost in Nampa typically arrives around October 13 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.

What hardiness zone is Nampa in?

Nampa is in USDA hardiness zone 7a. In zone 7a, winters are moderate — most common vegetables grow well in season.

How long is the growing season in Nampa?

Nampa has about 167 frost-free days — a moderate growing season — between the average last spring frost (April 29) and first fall frost (October 13).

When should I plant tomatoes in Nampa?

For Nampa, sow tomatoes indoors about March 4–March 18 and move the seedlings out around May 6, after the last spring frost.

Planting reminders

Never miss a window in Nampa

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

Nearby cities

8 within reach

Frost dates recorded at NAMPA SUGAR FACTORY, 2 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 Nampa, ID — Frost Dates & Zone 7a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00106305. Retrieved from https://blissgarden.com/idaho/nampa.