When to Plant Sunchoke in Knox County, IN
Sunchokes (Jerusalem artichokes) are a native sunflower relative grown for their knobby, nutty-flavored tubers. They are extremely productive and nearly impossible to eradicate.
Knox County, Indiana is in USDA Zone 6a. The average last spring frost is April 10 and the first fall frost is October 23, giving you a growing season of approximately 196 days.
At an elevation of 735 feet, Knox County receives approximately 38.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Sunchoke during the growing season.
Knox County Soil Profile
Soil Type
Silt Loam
Soil pH
6-7.2
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
Sunchoke Planting Timeline — Knox County, IN
Sunchoke Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 24 | Apr 24 – May 8 |
| Harvest | August 14 | Aug 14 – Oct 9 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | — |
| July | — |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| 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 6a
Growing Season
196 days
Growing Tips for Knox 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 Knox County, IN?
Knox County is in Zone 6a with an average last frost of April 10. Plan your Sunchoke planting based on this frost date — see the calendar above for exact timing.
What planting zone is Knox County, IN?
Knox County, Indiana is in USDA Hardiness Zone 6a. The average last spring frost is April 10 and first fall frost is October 23.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Knox County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.
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