Frost dates for ZIP 81639 (Hayden, CO)
Average last spring and first fall frost dates with 10%, 50% and 90% odds, from NOAA's 1991–2020 climate normals for the nearest weather station, Hayden, CO (5 miles away).
- Average last spring frostJun 150% chance of a 32°F freeze after this date
- Average first fall frostSep 2050% chance of a 32°F freeze by this date
- Growing season (frost-free)109 daysmedian, 32°F threshold
- USDA hardiness zone5a-20 to -15°F avg. coldest night
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This week in your yard
As of Oct 17, 2026, from your frost dates, zone and soil temperature. Lawn timing · Vegetables · Pruning · Plants
Soil temperature now
2-inch depth
No soil station with a fresh reading within 62 miles.
4-inch depth
No soil station with a fresh reading within 62 miles.
Fall: Texas A&M AgriLife times fall pre-emergent (for winter weeds such as annual bluegrass) to soil cooling to about 70°F for several days. The 50–55°F band is the spring trigger. Always read and follow the product label.
7-day forecast and frost risk
The latest National Weather Service 7-day forecast and any Frost Advisory or Freeze Warning for 81639 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
No soil reading near this ZIP. Typical extension timing for your region: spring mid-April to mid-May.
Fertilizer window
Lawn region: Mountain West and High Plains. Timing only; always follow the product label.
- Kentucky bluegrass (cool-season): Early fall: Around Labor Day (late August–September); Late fall: Late October–November, before the ground freezes; Late spring: Optional around Memorial Day. Avoid: Early-spring and midsummer feeding (pushes top growth, favors crabgrass).
Plant now
No vegetable planting windows are open this week.
Prune now
No frost-timed pruning windows are open this week.
Spring-flowering shrubs are pruned right after their flowers fade, not by date. See the pruning guide.
Last spring frost odds
| Chance of a 32°F freeze after this date | Date |
|---|---|
| 90% (early: most years still freeze after this) | May 15 |
| 50% (the "average" last frost) | Jun 1 |
| 10% (cautious: only 1 year in 10 freezes later) | Jun 16 |
Most gardeners plant frost-tender crops (tomatoes, peppers, basil) after the 50% date, and closer to the 10% date for less risk.
First fall frost odds
| Chance the first 32°F freeze has happened by this date | Date |
|---|---|
| 10% (early: 1 year in 10 freezes this soon) | Sep 7 |
| 50% (the "average" first frost) | Sep 20 |
| 90% (late: most years have frozen by now) | Sep 30 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | Jun 17 | Sep 10 |
| 32°F (freeze) | Jun 1 | Sep 20 |
| 28°F (hard freeze) | May 13 | Sep 29 |
n/a means NOAA did not publish a date at that threshold for this station (usually because it rarely gets that cold).
Vegetable planting calendar for 81639
Dates count from your average last spring frost (Jun 1) and first fall frost (Sep 20). Half of years have a frost after the spring date, so give tender crops (tomatoes, peppers, squash) some slack.
| Crop | Start indoors | Spring planting | Fall planting |
|---|---|---|---|
| Tomato | Apr 6–20 | Jun 8–22 (transplant) | – |
| Pepper (sweet and hot) | Mar 23–Apr 6 | Jun 15–29 (transplant) | – |
| Eggplant | Mar 23–Apr 6 | Jun 15–29 (transplant) | – |
| Tomatillo | Apr 6–20 | Jun 8–22 (transplant) | – |
| Lettuce | Apr 6–20 | May 11–Jun 1 (transplant) May 4–Jun 15 (sow outdoors) | Jul 26–Aug 16 (transplant) Jul 12–Aug 9 (sowing) |
| Spinach | – | Apr 20–May 11 (sow outdoors) | Jul 26–Aug 16 (sowing) |
| Kale | Apr 6–20 | May 4–18 (transplant) May 4–18 (sow outdoors) | Jun 28–Jul 26 (transplant) Jun 14–Jul 12 (sowing) |
| Collards | Apr 6–20 | May 4–Jun 1 (transplant) May 4–Jun 1 (sow outdoors) | Jun 28–Jul 26 (transplant) Jun 14–Jul 12 (sowing) |
| Broccoli | Mar 23–Apr 6 | May 4–18 (transplant) | Jun 14–Jul 12 (transplant) |
| Cabbage | Mar 23–Apr 6 | May 4–18 (transplant) | Jun 14–Jul 12 (transplant) |
| Cauliflower | Mar 23–Apr 6 | May 18–Jun 1 (transplant) | Jun 14–Jul 12 (transplant) |
| Brussels sprouts | Mar 9–23 | May 4–18 (transplant) | May 31–Jun 21 (transplant) |
| Kohlrabi | Apr 6–20 | May 4–18 (transplant) May 4–18 (sow outdoors) | Jul 12–26 (sowing) |
| Bok choy / Asian greens | – | May 4–18 (sow outdoors) | Jul 26–Aug 9 (sowing) |
| Arugula | – | May 4–Jun 1 (sow outdoors) | Jul 26–Aug 23 (sowing) |
| Mustard greens | – | May 4–25 (sow outdoors) | Jul 26–Aug 9 (sowing) |
| Swiss chard | Apr 20–May 4 | May 18–Jun 8 (transplant) May 18–Jun 15 (sow outdoors) | Jul 12–26 (sowing) |
| Beet | – | May 4–Jun 1 (sow outdoors) | Jul 12–26 (sowing) |
| Carrot | – | May 11–Jun 8 (sow outdoors) | Jun 28–Jul 12 (sowing) |
| Radish | – | Apr 27–Jun 8 (sow outdoors) | Aug 9–23 (sowing) |
| Turnip | – | May 4–25 (sow outdoors) | Jul 12–26 (sowing) |
| Parsnip | – | May 11–Jun 1 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Apr 6–May 4 (sow outdoors) | Jun 28–Jul 12 (sowing) |
| Onion (bulbing) | Mar 9–23 | Apr 20–May 4 (transplant) | – |
| Green onion / scallion | – | Apr 20–May 18 (sow outdoors) | Jul 12–26 (sowing) |
| Leek | Mar 9–23 | May 4–18 (transplant) | – |
| Garlic | – | – | Aug 9–Sep 6 (sowing) |
| Shallot | – | Apr 20–May 4 (transplant) | Aug 9–Sep 6 (sowing) |
| Potato | – | May 4–18 (transplant) | May 31–Jun 14 (transplant) |
| Sweet potato | – | Jun 22–Jul 6 (transplant) | – |
| Sweet corn | – | Jun 8–22 (sow outdoors) | – |
| Bean, bush (snap) | – | Jun 8–22 (sow outdoors) | – |
| Bean, pole | – | Jun 8–22 (sow outdoors) | – |
| Lima bean | – | Jun 15–29 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | Jun 22–Jul 13 (sow outdoors) | – |
| Cucumber | May 4–11 | Jun 8–22 (transplant) Jun 8–22 (sow outdoors) | – |
| Summer squash / zucchini | May 4–11 | Jun 8–22 (transplant) Jun 8–22 (sow outdoors) | – |
| Winter squash | May 4–11 | Jun 8–22 (transplant) Jun 8–22 (sow outdoors) | – |
| Pumpkin | – | Jun 8–22 (sow outdoors) | – |
| Watermelon | May 4–11 | Jun 15–29 (transplant) Jun 15–29 (sow outdoors) | – |
| Cantaloupe / muskmelon | May 4–11 | Jun 15–29 (transplant) Jun 15–29 (sow outdoors) | – |
| Okra | Apr 20–May 4 | Jun 15–29 (transplant) Jun 15–29 (sow outdoors) | – |
| Celery | Mar 9–23 | Jun 8–15 (transplant) | – |
| Basil | Apr 20–May 4 | Jun 8–22 (transplant) Jun 8–22 (sow outdoors) | – |
| Cilantro | – | May 18–Jun 15 (sow outdoors) | Jul 26–Aug 9 (sowing) |
| Parsley | Mar 23–Apr 6 | May 18–Jun 1 (transplant) May 11–Jun 1 (sow outdoors) | – |
| Dill | – | Jun 1–15 (sow outdoors) | Jul 26–Aug 9 (sowing) |
| Sunflower | – | Jun 1–15 (sow outdoors) | – |
| Asparagus (crowns) | – | May 4–18 (transplant) | – |
| Rhubarb (crowns) | – | May 4–18 (transplant) | – |
| Strawberry (plants) | – | May 4–18 (transplant) | Jul 12–Aug 9 (transplant) |
Typical ranges from university extension planting calendars, adjusted to your frost dates. Probabilities, not guarantees. Fall windows that would overlap spring planting are left out, as are fall crops of frost-tender plants where the frost-free season is under 210 days.
Plants that do well here
Colorado has a university or garden plant program: Plant Select®. Plant frost-tender annuals after June 1 here (the average last frost). Not affiliated with the program.
Where these numbers come from
Station: Hayden, CO (NOAA GHCN-Daily ID USC00053867), elevation 6,467 ft, 5.0 miles from the ZIP's center point. NOAA completeness flag: S (standard, 24+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Craig Moffat Co AP, CO | 15 mi | Jun 6 | Sep 12 |
| Craig 4SW, CO | 20 mi | May 29 | Sep 20 |
| Steamboat Springs, CO | 23 mi | Jun 9 | Sep 12 |
The average last-frost dates of these stations span 11 days, a rough guide to local variation. See data sources & methods.
Frost questions for 81639
When is the last frost in 81639?
The average (50% chance) last spring freeze of 32°F for ZIP 81639 is June 1. For a more cautious planting date, use June 16, when only 1 year in 10 still sees a later freeze.
When is the first frost in 81639?
The average first fall freeze is September 20. In 1 year in 10 it comes by September 7.
What hardiness zone is 81639?
ZIP 81639 is in USDA zone 5a (-20 to -15°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 81639 right now?
This page shows the latest 2-inch and 4-inch soil temperature from the nearest public soil station (USDA SCAN, NOAA USCRN or TexMesonet), or a labeled estimate when no station is close, against the 50–55°F spring pre-emergent band.
Nearby ZIP codes
80487 Steamboat Springs 81653 80428 81625 Craig 81638 80469 Phippsburg 80467 Oak Creek 82332
Other ZIP codes in Routt County
80428 80463 80467 80469 80479 80483 80487 81653 All Routt County frost dates · Colorado frost dates
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