When to Plant Asparagus in Hillsborough County, NH
Asparagus is a long-lived perennial vegetable that produces tender spears each spring for 15-20 years once established. It requires patience but rewards with reliable harvests.
Hillsborough County, New Hampshire is in USDA Zone 5b. The average last spring frost is May 2 and the first fall frost is October 11, giving you a growing season of approximately 162 days.
At an elevation of 145 feet, Hillsborough County receives approximately 44 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Asparagus to ensure they mature before fall.
Hillsborough County Soil Profile
Soil Type
Silt Loam
Soil pH
4.9-6.6
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
Asparagus Planting Timeline — Hillsborough County, NH
Asparagus Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 16 | May 16 – May 30 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
730–1095 days
Soil pH
6.5 – 7.5
USDA Zone
Zone 5b
Growing Season
162 days
Growing Tips for Hillsborough County
Plant crowns in deep trenches with compost. Do not harvest spears for the first two years to allow root establishment. Mulch heavily to suppress weeds and retain moisture.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Asparagus in Other Locations
Frequently Asked Questions
When should I plant Asparagus in Hillsborough County, NH?
Hillsborough County is in Zone 5b with an average last frost of May 2. Plan your Asparagus planting based on this frost date — see the calendar above for exact timing.
What planting zone is Hillsborough County, NH?
Hillsborough County, New Hampshire is in USDA Hardiness Zone 5b. The average last spring frost is May 2 and first fall frost is October 11.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Hillsborough County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.
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