When to Plant Hubbard Squash in Washtenaw County, MI
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.
Washtenaw County, Michigan is in USDA Zone 6a. The average last spring frost is April 29 and the first fall frost is October 16, giving you a growing season of approximately 170 days.
At an elevation of 737 feet, Washtenaw County receives approximately 38 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Hubbard Squash during the growing season.
Washtenaw County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-7.2
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
Hubbard Squash Planting Timeline — Washtenaw County, MI
Hubbard Squash Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 25 | Mar 25 – Apr 8 |
| Transplant Outdoors | May 13 | May 13 – May 27 |
| Direct Sow | May 6 | May 6 – May 27 |
| Harvest | August 26 | Aug 26 – Sep 30 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | — |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| 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 6a
Growing Season
170 days
Growing Tips for Washtenaw 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 Washtenaw County, MI?
Washtenaw County is in Zone 6a with an average last frost of April 29. Plan your Hubbard Squash planting based on this frost date — see the calendar above for exact timing.
What planting zone is Washtenaw County, MI?
Washtenaw County, Michigan is in USDA Hardiness Zone 6a. The average last spring frost is April 29 and first fall frost is October 16.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Washtenaw County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.
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