Douglas 1 SE, WY Frost Dates & Growing Season

The two dates every Douglas 1 SE garden is planned around, plus ready-computed planting windows for the most popular crops.

Last spring frost
May 19
~50% chance of frost after
First fall frost
Sep 23
~50% chance of frost before
Growing season
127 days
frost-free stretch
USDA zone
≈ 5a
estimated from nearby reference
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost May 7 May 19 Jun 2
First fall frost Oct 6 Sep 23 Sep 10
Hard freeze (28°F), median last May 7 · first Oct 3

Computed from NOAA 1991–2020 climate normals at the DOUGLAS 1 SE station. "Safe" means frost past that date happens only about one year in ten. Your exact garden can still run days either way with elevation and terrain — check your own ZIP with the frost date lookup.

Planting windows for Douglas 1 SE

Computed from Douglas 1 SE's own frost dates. Click any crop for the full zone-5 growing guide — varieties, spacing, fall plantings, and more.

CropStart seeds indoorsTransplantDirect sow
🍅 Tomatoes Mar 24 – Apr 7 May 26 – Jun 2
🫑 Peppers Mar 10 – Mar 24 Jun 2 – Jun 9
🥬 Lettuce Apr 7 – Apr 21 Apr 21 – May 5 Apr 21 – May 19
🫛 Peas Apr 7 – Apr 21
🥕 Carrots Apr 28 – May 19
🥦 Broccoli Mar 31 – Apr 14 Apr 28 – May 12
🥬 Kale Apr 7 – Apr 21 Apr 21 – May 5 Apr 21 – May 5
🥒 Cucumbers Apr 21 – Apr 28 May 26 – Jun 2 May 26 – Jun 2
🥒 Zucchini Apr 21 – Apr 28 May 26 – Jun 2 May 26 – Jun 2
🫘 Green Beans (Bush) May 26 – Jun 2
🌽 Sweet Corn May 26 – Jun 2
🌿 Basil Apr 7 – Apr 21 May 26 – Jun 2 Jun 2 – Jun 9
🧄 Garlic Fall: Aug 12 – Sep 9

Want this for all 50 crops, or as a printable seed-shelf schedule? Use the planting calendar and the seed starting scheduler — both can use Douglas 1 SE's dates automatically after a lookup.

Reading the season in Douglas 1 SE

At about 127 frost-free days, Douglas 1 SE rewards efficiency: start warm-season crops indoors, favor short-season varieties, and lean on cold-tolerant crops — peas, kale, roots — that shrug off the shoulder-season frosts on either end.

Frequently asked questions

When is the last frost in Douglas 1 SE, WY?

The average last spring frost in Douglas 1 SE is around May 19, based on 1991–2020 climate normals. That's a median — about half of years see a later frost, so tender crops are safest going out a week or two after this date.

When is the first frost in Douglas 1 SE, WY?

The average first fall frost in Douglas 1 SE arrives around Sep 23. Crops still in the garden need to mature before then, and frost-tender plants need harvesting or protection as the date approaches.

How long is the growing season in Douglas 1 SE?

About 127 frost-free days on average, from May 19 to Sep 23. That favors short-season varieties and transplants for warm-season crops, with cool-season vegetables doing the heavy lifting in spring and fall.

What USDA zone is Douglas 1 SE in?

USDA zone 5a on the 2023 Plant Hardiness Zone Map. Note that zones describe winter cold, not frost timing — these frost dates are the numbers to plan plantings around.