When to plant Butternut Squash in Summit County, CO
In Summit County, Butternut Squash is a spring-only crop. Plant June 23–July 14 once soil hits 50°F.
When to Plant Butternut Squash in Summit County, CO
Butternut squash is a popular winter squash with a long neck, small seed cavity, and sweet, nutty orange flesh. It stores exceptionally well for months.
Summit County, Colorado is in USDA Zone 5a. The average last spring frost is June 16 and the first fall frost is September 4, giving you a growing season of approximately 80 days.
At an elevation of 7,005 feet, Summit County receives approximately 17.5 inches of rainfall annually with predominantly loam soil. Summer highs average 81°F, so choose short-season varieties of Butternut Squash to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Butternut Squash successfully. Mulch heavily to conserve soil moisture.
Summit County Soil Profile
Soil Type
Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Butternut Squash Planting Timeline — Summit County, CO
Butternut Squash Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | May 12 | May 12 – May 26 |
| Transplant Outdoors | June 30 | Jun 30 – Jul 14 |
| Direct Sow | June 23 | Jun 23 – Jul 14 |
| Harvest | September 29 | Sep 29 – Nov 3 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Start Indoors |
| June | Transplant Outdoors Direct Sow |
| July | Transplant Outdoors Direct Sow |
| August | — |
| September | Harvest |
| October | Harvest |
| November | Harvest |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
85–110 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 5a
📆 Growing Season
80 days in Summit County
Growing Tips for Summit County
Start seeds indoors 3 weeks early or direct sow after frost. Allow 6-8 feet for sprawling vines. Harvest when the skin is hard and uniformly tan. Cure in the sun for 10 days.
Companion Planting
Good Companions
Avoid Planting Near
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Butternut Squash in Other Locations
Frequently Asked Questions
When should I plant Butternut Squash in Summit County, CO?
Summit County is in Zone 5a with an average last frost of June 16. Plan your Butternut Squash planting based on this frost date — see the calendar above for exact timing.
What planting zone is Summit County, CO?
Summit County, Colorado is in USDA Hardiness Zone 5a. The average last spring frost is June 16 and first fall frost is September 4.
When should I plant Butternut Squash in Summit County, CO?
In Summit County, CO, plant Butternut Squash after the last frost (around June 16) and before the first frost (around September 4). Best results when soil holds above 50°F.
What growing zone is Summit County, CO for Butternut Squash?
Summit County sits in USDA Zone 5a. Butternut Squash grows reliably in zones 3a through 11b, so it's a good fit here.
Can Butternut Squash grow in Summit County's climate?
Yes — Butternut Squash grows well in Summit County's temperate climate. Summit County averages a 80-day frost-free season, with last frost around June 16 and first frost around September 4.
Your Summit County Garden Planner — Free
A 22-page printable planner built for Summit County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.