When is the last frost in Nampa, ID?

The average last spring frost (50% probability of 32°F) in Nampa is around April 29, based on NOAA/NCEI 1991–2020 normals at the Nampa Sugar Factory, ID station (2.9 mi away). Half of years it falls outside that date, so wait 1–2 weeks past it before setting out frost-tender plants.

When is the first fall frost in Nampa?

The average first fall frost in Nampa, ID is around October 13, giving roughly a 164-day frost-free growing season.

What planting zone is Nampa, ID?

Nampa is in USDA plant hardiness zone 7a (average annual extreme minimum temperature 0 to 5°F), from the 2023 USDA Plant Hardiness Zone Map.

What is the weather like in Nampa?

In Nampa, ID the warmest month is July (avg high 93.3°F) and the coldest is December (avg low 22.8°F). It averages about 11″ of precipitation a year and 9.7″ of snow.

Home › Idaho › Nampa

Nampa, ID Planting Calendar & Frost Dates

USDA hardiness zone 7a · ZIP 83651 · elevation 753′ · NOAA & USDA data

Nampa is in USDA hardiness zone 7a (winters can dip to 0 to 5°F), with a growing season of about 164 days between the average last spring frost (April 29) and first fall frost (October 13). The warmest month is July (avg high 93.3°F); the coldest is December (avg low 22.8°F). It averages 11″ of precipitation a year and 9.7″ of snow, mostly mid-winter. Start cool-season crops several weeks before the last frost; wait until after it for tomatoes, peppers and other tender crops.

Hardiness zone

min temp 0 to 5°F

Last spring frost

April 29

avg (50% prob, 32°F)

First fall frost

October 13

avg (50% prob, 32°F)

Growing season

164 days

frost-free window

Warmest month

July

avg high 93.3°F

Month-by-month typical weather in Nampa

Average conditions from the NOAA/NCEI 1991–2020 U.S. Climate Normals at Nampa Sugar Factory, ID (2.9 mi away). Temperatures °F, precipitation & snow in inches.

Month	Avg high	Avg low	Mean	Precip (in)	Snow (in)
January	39.5	23	31.2	1.4	3.4
February	47.2	26	36.6	1	1.4
March	57.4	31.6	44.5	1.3	0.2
April	64.5	36.1	50.3	1.1	0
May	73.9	44	58.9	1.4	0
June	82.8	51	66.9	0.7	0
July	93.3	57.3	75.3	0.3	0
August	91.6	55.5	73.6	0.2	0
September	81	46.5	63.8	0.4	0
October	66.6	36.5	51.5	0.8	0
November	50.7	28.4	39.5	1.2	0.5
December	40	22.8	31.4	1.4	4.2

What to plant when in Nampa

Crop	Season	What to do & when
Tomatoes	warm	Start seeds indoors: March 18 · Transplant out: May 6
Peppers	warm	Start seeds indoors: March 4 · Transplant out: May 13
Cucumbers	warm	Direct sow: May 6
Zucchini / squash	warm	Direct sow: May 6
Bush beans	warm	Direct sow: May 6
Sweet corn	warm	Direct sow: May 6
Basil	warm	Transplant out: May 6
Peas	cool	Sow (spring): March 25 · Sow (fall): August 18
Spinach	cool	Sow (spring): March 18 · Sow (fall): August 18
Lettuce	cool	Sow (spring): April 1 · Sow (fall): August 18
Kale	cool	Transplant (spring): April 8 · Sow (fall): August 4
Broccoli	cool	Transplant (spring): April 15
Carrots	cool	Sow (spring): April 8 · Sow (fall): August 4
Onions	cool	Transplant (spring): April 1
Potatoes	cool	Plant seed potatoes: April 15
Radishes	cool	Sow (spring): April 1 · Sow (fall): September 1

Dates are computed from Nampa's average frost dates using standard cool-/warm-season timing. They're a starting point — a cold spring, a warm microclimate, or a fast-maturing variety can shift them by a week or two.

Want the exact dates for your yard? →
Look up your precise ZIP-code frost dates and a full 26-crop planting calendar on our free interactive tool.
Open the frost & planting tool

🌾 Get a frost reminder

One email in early spring and early fall with the dates for your area. No spam.

Gear that helps you plant on time

Some links below are Amazon affiliate links (tag theboringthin-20). If you buy through them we may earn a small commission at no extra cost to you — it keeps this almanac free. We only list generic, genuinely-useful categories.

Soil thermometer →Know when the ground is warm enough to sow — the honest signal, not the calendar.Seed-starting trays + dome →Start tomatoes & peppers indoors on the schedule below.Seedling heat mat →Warms the soil for faster, more even germination indoors.Floating row cover / frost cloth →Buys you 4–8°F to beat an early or late frost.Raised garden bed kit →Warms and drains faster in spring than in-ground soil.Garden gloves →Basic kit for transplant day.

Nearby cities in Idaho

Caldwell, ID Meridian, ID Twin Falls, ID Pocatello, ID Idaho Falls, ID

Sources & method. Hardiness zone: 2023 USDA Plant Hardiness Zone Map (PRISM Climate Group, Oregon State University). Frost dates & growing season: NOAA/NCEI 1991–2020 U.S. Climate Normals, nearest station with published freeze normals — Nampa Sugar Factory, ID, 2.9 mi (confidence: high). Monthly weather normals: Nampa Sugar Factory, ID, 2.9 mi (confidence: high). ZIP centroid from U.S. Census 2023 ZCTA data. Frost dates are the 50%-probability date — half of years frost occurs outside the stated date. Nothing here is invented; where the nearest station is far, we say so. Last updated 2026-07-22.