Kim 10SSE, CO Frost Dates & Growing Season

The two dates every Kim 10SSE garden is planned around, plus ready-computed planting windows for the most popular crops.

Last spring frost
Apr 24
~50% chance of frost after
First fall frost
Oct 18
~50% chance of frost before
Growing season
177 days
frost-free stretch
USDA zone
≈ 6b
estimated from nearby reference
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Apr 10 Apr 24 May 6
First fall frost Oct 29 Oct 18 Oct 4
Hard freeze (28°F), median last Apr 11 · first Oct 28

Computed from NOAA 1991–2020 climate normals at the KIM 10SSE 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 Kim 10SSE

Computed from Kim 10SSE's own frost dates. Click any crop for the full zone-6 growing guide — varieties, spacing, fall plantings, and more.

CropStart seeds indoorsTransplantDirect sow
🍅 Tomatoes Feb 27 – Mar 13 May 1 – May 8
🫑 Peppers Feb 13 – Feb 27 May 8 – May 15
🥬 Lettuce Mar 13 – Mar 27 Mar 27 – Apr 10 Mar 27 – Apr 24
🫛 Peas Mar 13 – Mar 27
🥕 Carrots Apr 3 – Apr 24
🥦 Broccoli Mar 6 – Mar 20 Apr 3 – Apr 17
🥬 Kale Mar 13 – Mar 27 Mar 27 – Apr 10 Mar 27 – Apr 10
🥒 Cucumbers Mar 27 – Apr 3 May 1 – May 8 May 1 – May 8
🥒 Zucchini Mar 27 – Apr 3 May 1 – May 8 May 1 – May 8
🫘 Green Beans (Bush) May 1 – May 8
🌽 Sweet Corn May 1 – May 8
🌿 Basil Mar 13 – Mar 27 May 1 – May 8 May 8 – May 15
🧄 Garlic Fall: Sep 6 – Oct 4

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 Kim 10SSE's dates automatically after a lookup.

Reading the season in Kim 10SSE

Roughly 177 frost-free days gives Kim 10SSE gardeners room for nearly every common vegetable. Warm-season crops go out after Apr 24; a fall garden sown in late summer matures comfortably before the Oct 18 frost.

Frequently asked questions

When is the last frost in Kim 10SSE, CO?

The average last spring frost in Kim 10SSE is around Apr 24, 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 Kim 10SSE, CO?

The average first fall frost in Kim 10SSE arrives around Oct 18. 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 Kim 10SSE?

About 177 frost-free days on average, from Apr 24 to Oct 18. That fits nearly all common vegetables, though the longest-season melons and sweet potatoes benefit from transplants.

What USDA zone is Kim 10SSE in?

USDA zone 6b 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.