When to Plant Sunchoke in Union County, AR
Sunchokes (Jerusalem artichokes) are a native sunflower relative grown for their knobby, nutty-flavored tubers. They are extremely productive and nearly impossible to eradicate.
Union County, Arkansas is in USDA Zone 8a. The average last spring frost is March 22 and the first fall frost is November 3, giving you a growing season of approximately 226 days.
At an elevation of 508 feet, Union County receives approximately 52 inches of rainfall annually with predominantly silt loam soil. Summer highs average 92°F, providing good warmth for Sunchoke during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sunchoke root diseases.
Union County Soil Profile
Soil Type
Silt Loam
Soil pH
5.8-6.6
Drainage
Well Drained
Monthly Watering Guide for Sunchoke
Sunchoke needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Sunchoke Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.8" | 0" | ❄️ Dormant |
| Feb | — | 4.5" | 0" | ❄️ Dormant |
| Mar | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| May | 4.3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Oct | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Nov | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Dec | — | 3.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Union County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Sunchoke Planting Timeline — Union County, AR
Sunchoke Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 5 | Apr 5 – Apr 19 |
| Harvest | July 26 | Jul 26 – Sep 20 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | — |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
110–150 days
🧪 Soil pH
Needs 6–7.5 · Your soil: N/A
🗺️ USDA Zone
Zone 8a
📆 Growing Season
226 days in Union County
Growing Tips for Union 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
Check more plant combinations with our Companion Planting Checker →
Sunchoke in Other Locations
Frequently Asked Questions
When should I plant Sunchoke in Union County, AR?
Union County is in Zone 8a with an average last frost of March 22. Plan your Sunchoke planting based on this frost date — see the calendar above for exact timing.
What planting zone is Union County, AR?
Union County, Arkansas is in USDA Hardiness Zone 8a. The average last spring frost is March 22 and first fall frost is November 3.
Plan Your Garden with Confidence
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