Bonny Dam 2NE, CO Frost Dates & Growing Season

The two dates every Bonny Dam 2NE garden is planned around, plus ready-computed planting windows for the most popular crops.

Last spring frost
May 5
~50% chance of frost after
First fall frost
Oct 10
~50% chance of frost before
Growing season
158 days
frost-free stretch
USDA zone
≈ 6a
estimated from nearby reference
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Apr 21 May 5 May 19
First fall frost Oct 21 Oct 10 Sep 28
Hard freeze (28°F), median last Apr 25 · first Oct 18

Computed from NOAA 1991–2020 climate normals at the BONNY DAM 2NE 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 Bonny Dam 2NE

Computed from Bonny Dam 2NE'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 Mar 10 – Mar 24 May 12 – May 19
🫑 Peppers Feb 24 – Mar 10 May 19 – May 26
🥬 Lettuce Mar 24 – Apr 7 Apr 7 – Apr 21 Apr 7 – May 5
🫛 Peas Mar 24 – Apr 7
🥕 Carrots Apr 14 – May 5
🥦 Broccoli Mar 17 – Mar 31 Apr 14 – Apr 28
🥬 Kale Mar 24 – Apr 7 Apr 7 – Apr 21 Apr 7 – Apr 21
🥒 Cucumbers Apr 7 – Apr 14 May 12 – May 19 May 12 – May 19
🥒 Zucchini Apr 7 – Apr 14 May 12 – May 19 May 12 – May 19
🫘 Green Beans (Bush) May 12 – May 19
🌽 Sweet Corn May 12 – May 19
🌿 Basil Mar 24 – Apr 7 May 12 – May 19 May 19 – May 26
🧄 Garlic Fall: Aug 29 – Sep 26

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 Bonny Dam 2NE's dates automatically after a lookup.

Reading the season in Bonny Dam 2NE

Roughly 158 frost-free days gives Bonny Dam 2NE gardeners room for nearly every common vegetable. Warm-season crops go out after May 5; a fall garden sown in late summer matures comfortably before the Oct 10 frost.

Frequently asked questions

When is the last frost in Bonny Dam 2NE, CO?

The average last spring frost in Bonny Dam 2NE is around May 5, 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 Bonny Dam 2NE, CO?

The average first fall frost in Bonny Dam 2NE arrives around Oct 10. 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 Bonny Dam 2NE?

About 158 frost-free days on average, from May 5 to Oct 10. That fits nearly all common vegetables, though the longest-season melons and sweet potatoes benefit from transplants.

What USDA zone is Bonny Dam 2NE in?

USDA zone 6a 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.