When to Plant Pumpkin in Jackson County, CO
Pumpkins are large-fruited squash varieties grown for eating, decoration, and seed production. They require ample space and a long, warm growing season.
Jackson County, Colorado is in USDA Zone 3b. The average last spring frost is June 13 and the first fall frost is September 4, giving you a growing season of approximately 83 days.
At an elevation of 5,388 feet, Jackson County receives approximately 20.9 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Pumpkin to ensure they mature before fall.
Jackson County Soil Profile
Soil Type
Loam
Soil pH
6.6-8.1
Drainage
Well Drained
Plant Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Pumpkin Planting Timeline — Jackson County, CO
Pumpkin Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | May 2 | May 2 – May 16 |
| Transplant Outdoors | July 4 | Jul 4 – Jul 18 |
| Direct Sow | June 27 | Jun 27 – Jul 18 |
| Harvest | October 3 | Oct 3 – Nov 7 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Start Indoors |
| June | Direct Sow |
| July | Transplant Outdoors Direct Sow |
| August | — |
| September | — |
| October | Harvest |
| November | Harvest |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
85–120 days
Soil pH
6 – 7.5
USDA Zone
Zone 3b
Growing Season
83 days
Growing Tips for Jackson County
Direct sow on mounds after last frost. Allow 6-10 feet between plants. Slip a board under developing fruit to prevent rot. Harvest when rind is hard and deep in color.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Pumpkin in Other Locations
Frequently Asked Questions
When should I plant Pumpkin in Jackson County, CO?
Jackson County is in Zone 3b with an average last frost of June 13. Plan your Pumpkin planting based on this frost date — see the calendar above for exact timing.
What planting zone is Jackson County, CO?
Jackson County, Colorado is in USDA Hardiness Zone 3b. The average last spring frost is June 13 and first fall frost is September 4.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Jackson County gardeners in Zone 3b organize planting dates, track what's growing, and never miss a planting window.
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