When to Plant Hubbard Squash in Rio Grande County, CO
Hubbard squash is a large, bumpy-skinned winter squash with dense, sweet, dry flesh ideal for baking and pies. The hard shell allows storage for 6 months or more.
Rio Grande County, Colorado is in USDA Zone 4b. The average last spring frost is May 31 and the first fall frost is September 19, giving you a growing season of approximately 111 days.
At an elevation of 6,254 feet, Rio Grande County receives approximately 15.8 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Hubbard Squash to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Hubbard Squash successfully. Mulch heavily to conserve soil moisture.
Rio Grande County Soil Profile
Soil Type
Loam
Soil pH
6.5-7.8
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 8/10 — consider drought-tolerant varieties and mulching
Hubbard Squash Planting Timeline — Rio Grande County, CO
Hubbard Squash Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 19 | Apr 19 – May 3 |
| Transplant Outdoors | June 21 | Jun 21 – Jul 5 |
| Direct Sow | June 14 | Jun 14 – Jul 5 |
| Harvest | October 4 | Oct 4 – Nov 8 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors |
| June | Transplant Outdoors 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
100–120 days
Soil pH
6 – 7
USDA Zone
Zone 4b
Growing Season
111 days
Growing Tips for Rio Grande County
Start seeds indoors in short-season areas. Requires ample space and rich soil. Harvest when the skin is very hard and the color is deep. Cure in the sun before storing.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Hubbard Squash in Other Locations
Frequently Asked Questions
When should I plant Hubbard Squash in Rio Grande County, CO?
Rio Grande County is in Zone 4b with an average last frost of May 31. Plan your Hubbard Squash planting based on this frost date — see the calendar above for exact timing.
What planting zone is Rio Grande County, CO?
Rio Grande County, Colorado is in USDA Hardiness Zone 4b. The average last spring frost is May 31 and first fall frost is September 19.
Plan Your Garden with Confidence
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