When to Plant Sunchoke in Sullivan County, NH
Sunchokes (Jerusalem artichokes) are a native sunflower relative grown for their knobby, nutty-flavored tubers. They are extremely productive and nearly impossible to eradicate.
Sullivan County, New Hampshire is in USDA Zone 5a. The average last spring frost is May 12 and the first fall frost is October 7, giving you a growing season of approximately 148 days.
At an elevation of 495 feet, Sullivan County receives approximately 39.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Sunchoke to ensure they mature before fall.
Sullivan County Soil Profile
Soil Type
Silt Loam
Soil pH
5-6.6
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
Sunchoke Planting Timeline — Sullivan County, NH
Sunchoke Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 26 | May 26 – Jun 9 |
| Harvest | September 15 | Sep 15 – Nov 10 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | Transplant Outdoors |
| July | — |
| August | — |
| September | Harvest |
| October | Harvest |
| November | Harvest |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
110–150 days
Soil pH
6 – 7.5
USDA Zone
Zone 5a
Growing Season
148 days
Growing Tips for Sullivan County
Plant tubers 4 inches deep in early spring. Contain plants with barriers as they spread aggressively. Harvest after frost or leave in ground and dig as needed through winter.
Companion Planting
Good Companions
Level Up Your Garden
Sunchoke in Other Locations
Frequently Asked Questions
When should I plant Sunchoke in Sullivan County, NH?
Sullivan County is in Zone 5a with an average last frost of May 12. Plan your Sunchoke planting based on this frost date — see the calendar above for exact timing.
What planting zone is Sullivan County, NH?
Sullivan County, New Hampshire is in USDA Hardiness Zone 5a. The average last spring frost is May 12 and first fall frost is October 7.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Sullivan County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.
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