When to Plant Onion in Hampden County, MA
Onions are a fundamental kitchen staple available in yellow, white, and red varieties. Choose long-day, short-day, or intermediate types based on your latitude.
Hampden County, Massachusetts is in USDA Zone 6a. The average last spring frost is April 30 and the first fall frost is October 17, giving you a growing season of approximately 170 days.
At an elevation of 474 feet, Hampden County receives approximately 47.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Onion during the growing season.
Hampden County Soil Profile
Soil Type
Silt Loam
Soil pH
5.1-6.4
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
Onion Planting Timeline — Hampden County, MA
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 26 | Mar 26 – Apr 9 |
| Transplant Outdoors | April 30 | Apr 30 – May 14 |
| Direct Sow | April 16 | Apr 16 – May 7 |
| Fall Sowing | August 8 | Aug 8 – Aug 22 |
| Harvest | July 30 | Jul 30 – Sep 17 |
Plant 1" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
90–120 days
Soil pH
6 – 7
USDA Zone
Zone 6a
Growing Season
170 days
Growing Tips for Hampden County
Start seeds indoors 8-10 weeks before transplanting. Match day-length type to your latitude. Stop watering when tops begin to fall over and cure bulbs for 2-3 weeks before storage.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Onion in Other Locations
Frequently Asked Questions
When should I plant Onion in Hampden County, MA?
Hampden County is in Zone 6a with an average last frost of April 30. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is Hampden County, MA?
Hampden County, Massachusetts is in USDA Hardiness Zone 6a. The average last spring frost is April 30 and first fall frost is October 17.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Hampden County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.
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