When is the last frost in Grand Junction, CO?

The average last spring frost (50% probability of 32°F) in Grand Junction is around April 14, based on NOAA/NCEI 1991–2020 normals at the Grand Junction Wfo, CO station (3.5 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 Grand Junction?

The average first fall frost in Grand Junction, CO is around October 23, giving roughly a 190-day frost-free growing season.

What planting zone is Grand Junction, CO?

Grand Junction 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 Grand Junction?

In Grand Junction, CO the warmest month is July (avg high 94.5°F) and the coldest is January (avg low 17.3°F). It averages about 9.1″ of precipitation a year and 17.7″ of snow.

Home › Colorado › Grand Junction

Grand Junction, CO Planting Calendar & Frost Dates

USDA hardiness zone 7a · ZIP 81501 · elevation 1481′ · NOAA & USDA data

Grand Junction is in USDA hardiness zone 7a (winters can dip to 0 to 5°F), with a growing season of about 190 days between the average last spring frost (April 14) and first fall frost (October 23). The warmest month is July (avg high 94.5°F); the coldest is January (avg low 17.3°F). It averages 9.1″ of precipitation a year and 17.7″ 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 14

avg (50% prob, 32°F)

First fall frost

October 23

avg (50% prob, 32°F)

Growing season

190 days

frost-free window

Warmest month

July

avg high 94.5°F

Month-by-month typical weather in Grand Junction

Average conditions from the NOAA/NCEI 1991–2020 U.S. Climate Normals at Grand Junction Walker Fld, CO (4.3 mi away). Temperatures °F, precipitation & snow in inches.

Month	Avg high	Avg low	Mean	Precip (in)	Snow (in)
January	38.1	17.3	27.7	0.6	4.5
February	46.4	24.1	35.3	0.5	2.9
March	58.3	31.7	45	0.8	1.8
April	65.8	38.1	51.9	1	0.9
May	76.8	47.1	62	0.8	0.1
June	89.2	56.8	73	0.4	0
July	94.5	63.9	79.2	0.6	0
August	90.9	61.6	76.3	0.9	0
September	81.7	52.5	67.1	1.2	0
October	66.9	39.5	53.2	1	0.4
November	51.8	27.5	39.6	0.6	1.9
December	38.8	18	28.4	0.6	5.2

What to plant when in Grand Junction

Crop	Season	What to do & when
Tomatoes	warm	Start seeds indoors: March 3 · Transplant out: April 21
Peppers	warm	Start seeds indoors: February 17 · Transplant out: April 28
Cucumbers	warm	Direct sow: April 21
Zucchini / squash	warm	Direct sow: April 21
Bush beans	warm	Direct sow: April 21
Sweet corn	warm	Direct sow: April 21
Basil	warm	Transplant out: April 21
Peas	cool	Sow (spring): March 10 · Sow (fall): August 28
Spinach	cool	Sow (spring): March 3 · Sow (fall): August 28
Lettuce	cool	Sow (spring): March 17 · Sow (fall): August 28
Kale	cool	Transplant (spring): March 24 · Sow (fall): August 14
Broccoli	cool	Transplant (spring): March 31
Carrots	cool	Sow (spring): March 24 · Sow (fall): August 14
Onions	cool	Transplant (spring): March 17
Potatoes	cool	Plant seed potatoes: March 31
Radishes	cool	Sow (spring): March 17 · Sow (fall): September 11

Dates are computed from Grand Junction'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 Colorado

Arvada, CO Boulder, CO Littleton, CO Broomfield, CO Westminster, CO Denver, CO Longmont, CO Loveland, CO

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 — Grand Junction Wfo, CO, 3.5 mi (confidence: high). Monthly weather normals: Grand Junction Walker Fld, CO, 4.3 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.