Blue Mesa Lake, CO Frost Dates & Growing Season

The two dates every Blue Mesa Lake garden is planned around, plus ready-computed planting windows for the most popular crops.

Last spring frost
Jun 9
~50% chance of frost after
First fall frost
Sep 16
~50% chance of frost before
Growing season
99 days
frost-free stretch
USDA zone
≈ 5b
estimated from nearby reference
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost May 26 Jun 9 Jun 24
First fall frost Sep 27 Sep 16 Sep 3
Hard freeze (28°F), median last May 25 · first Sep 27

Computed from NOAA 1991–2020 climate normals at the BLUE MESA LAKE 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 Blue Mesa Lake

Computed from Blue Mesa Lake'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 Apr 14 – Apr 28 Jun 16 – Jun 23
🫑 Peppers Mar 31 – Apr 14 Jun 23 – Jun 30
🥬 Lettuce Apr 28 – May 12 May 12 – May 26 May 12 – Jun 9
🫛 Peas Apr 28 – May 12
🥕 Carrots May 19 – Jun 9
🥦 Broccoli Apr 21 – May 5 May 19 – Jun 2
🥬 Kale Apr 28 – May 12 May 12 – May 26 May 12 – May 26
🥒 Cucumbers May 12 – May 19 Jun 16 – Jun 23 Jun 16 – Jun 23
🥒 Zucchini May 12 – May 19 Jun 16 – Jun 23 Jun 16 – Jun 23
🫘 Green Beans (Bush) Jun 16 – Jun 23
🌽 Sweet Corn Jun 16 – Jun 23
🌿 Basil Apr 28 – May 12 Jun 16 – Jun 23 Jun 23 – Jun 30
🧄 Garlic Fall: Aug 5 – Sep 2

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 Blue Mesa Lake's dates automatically after a lookup.

Reading the season in Blue Mesa Lake

At about 99 frost-free days, Blue Mesa Lake 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 Blue Mesa Lake, CO?

The average last spring frost in Blue Mesa Lake is around Jun 9, 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 Blue Mesa Lake, CO?

The average first fall frost in Blue Mesa Lake arrives around Sep 16. 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 Blue Mesa Lake?

About 99 frost-free days on average, from Jun 9 to Sep 16. 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 Blue Mesa Lake in?

USDA zone 5b 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.