Deconstruct Sun

Grand Junction, CO: Hardiness Zone 7a & Sunlight by Season

Grand Junction is in USDA hardiness zone 7a. Here’s what that means for winter, plus sunrise, sunset, daylight hours and the sun’s path through the year.

Hardiness zone
7a
2023 USDA map
Coldest winter night (avg)
0 to 5 °F
−17.8 to −15.0 °C
Longest day (Jun 21)
14h 55m
5:48 AM – 8:43 PM
Shortest day (Dec 21)
9h 25m
7:29 AM – 4:55 PM

Zone 7a in Grand Junction

On the 2023 USDA Plant Hardiness Zone Map, Grand Junction falls in zone 7a. That means the coldest night of a typical winter drops to between 0 and 5 °F. Perennials, shrubs and trees labeled for zone 7a or colder (a lower number) should survive the winter here.

A zone only covers winter cold. For a plant to do well it also needs the right amount of sun, and that varies far more from one corner of a yard to the next than the zone does across town.

This is not the official USDA Plant Hardiness Zone Map. Zones are derived from the official 2023 dataset, resampled to about 2 km.

Nearby cities

All Colorado hardiness zones →

The sun over Grand Junction

On the June solstice the sun rises in the northeast at 5:48 AM and climbs to 74° above the horizon at 1:16 PM. On the December solstice the noon sun reaches only 28°, so a 20-foot tree casts a noon shadow about 38 feet long. In June the same tree’s noon shadow is only 6 feet.

0°15°30°45°60°75°90°NNEESESSWWNWN
June solsticeMarch & September equinoxDecember solstice

Open the interactive sun calculator for Grand Junction

Sunrise, sunset & daylight by month

DateSunriseSunsetDaylightNoon sun
Jan 217:28 AM5:22 PM9h 54m31°
Feb 216:57 AM5:58 PM11h 01m41°
Mar 217:15 AM7:27 PM12h 12m51°
Apr 216:28 AM7:57 PM13h 29m63°
May 215:56 AM8:25 PM14h 30m71°
Jun 215:48 AM8:43 PM14h 55m74°
Jul 216:05 AM8:35 PM14h 30m71°
Aug 216:33 AM8:00 PM13h 28m63°
Sep 217:01 AM7:12 PM12h 11m51°
Oct 217:30 AM6:26 PM10h 57m40°
Nov 217:04 AM4:55 PM9h 52m31°
Dec 217:29 AM4:55 PM9h 25m28°

Local time (Denver), including daylight saving time. “Noon sun” is the sun’s height above the horizon at solar noon.

Daylight through the year

0h6h12h18h24hJanuary: 9h 54mJanFebruary: 11h 01mFebMarch: 12h 12mMarApril: 13h 29mAprMay: 14h 30mMayJune: 14h 55mJunJuly: 14h 30mJulAugust: 13h 28mAugSeptember: 12h 11mSepOctober: 10h 57mOctNovember: 9h 52mNovDecember: 9h 25mDec

What “full sun” means in Grand Junction

Full sun is 6+ hours of direct sun. In Grand Junction an open spot has 14.9 hours of daylight to work with in June and 9.4 in December, so a bed that clears 6 hours in summer can easily drop to part shade in winter once the low sun slips behind trees and houses.

Full sun6+ hoursof direct sun
Part sun4–6 hoursof direct sun
Part shade2–4 hoursof direct sun
Full shadeUnder 2 hoursof direct sun

Measure the sun in your Grand Junction yard

Daylight is the ceiling. Deconstruct Sun traces the trees and buildings around one exact spot and tells you its real direct-sun hours, today and at every solstice and equinox.

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Questions

What hardiness zone is Grand Junction, CO in?

Grand Junction, Colorado is in USDA plant hardiness zone 7a on the 2023 map. The average coldest winter night is 0 to 5 °F (−17.8 to −15.0 °C).

How many hours of daylight does Grand Junction get?

About 14.9 hours on the June solstice (sunrise 5:48 AM, sunset 8:43 PM) and 9.4 hours on the December solstice (sunrise 7:29 AM, sunset 4:55 PM). Around the equinoxes it is close to 12 hours.

How many hours of sun does my Grand Junction yard get?

Up to the daylight hours above, minus whatever trees, buildings and fences block. In winter, when the sun stays low, that can be most of it. The Deconstruct Sun iPhone app measures the real direct-sun hours for one exact spot by having you trace what is around it.

When is the best time to plant in Grand Junction?

Zone 7a tells you which perennials survive winter, not planting dates. For timing, use your local average frost dates from your county extension office, and choose plants rated for zone 7a or colder.

Source: USDA Plant Hardiness Zone Map, 2023. Agricultural Research Service, U.S. Department of Agriculture, planthardiness.ars.usda.gov. Underlying data © PRISM Group, Oregon State University, prism.oregonstate.edu, accessed 2026-08-30. Sun times calculated for 39.089, -108.567.