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When to Plant Sunchoke in Coal County, OK

Sunchokes (Jerusalem artichokes) are a native sunflower relative grown for their knobby, nutty-flavored tubers. They are extremely productive and nearly impossible to eradicate.

Coal County, Oklahoma is in USDA Zone 7b. The average last spring frost is March 28 and the first fall frost is November 2, giving you a growing season of approximately 219 days.

At an elevation of 892 feet, Coal County receives approximately 28.5 inches of rainfall annually with predominantly loam soil. Summer highs average 89°F, providing good warmth for Sunchoke during the growing season.

Coal County, OK (Zone 7b) Long season
219 days
Last Spring Frost March 28
219 growing days
First Fall Frost November 2

Coal County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.2

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 0.7" 0" ❄️ Dormant
Feb 1" 0" ❄️ Dormant
Mar 4.3" 1.6" 2.7" 🚿 Regular watering
Apr 4.3" 2.7" 1.6" 💧 Light watering
May 4.3" 4.2" 0.1" 💧 Light watering
Jun 4.3" 4.8" 0" ✅ Rainfall sufficient
Jul 4.3" 3.7" 0.6" 💧 Light watering
Aug 4.3" 3.6" 0.7" 💧 Light watering
Sep 4.3" 2.8" 1.5" 💧 Light watering
Oct 4.3" 1.9" 2.4" 🚿 Regular watering
Nov 4.3" 1" 3.3" 🚿 Regular watering
Dec 0.7" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Coal County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Sunchoke Planting Timeline — Coal County, OK

Sunchoke Planting Calendar

Activity When Date Range
Transplant Outdoors April 11 Apr 11 – Apr 25
Harvest August 1 Aug 1 – Sep 26

Plant 1" deep · 30" apart · Rows 42" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Transplant Outdoors
May
June
July
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 7b

📆 Growing Season

219 days in Coal County

Growing Tips for Coal 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 →

Frequently Asked Questions

When should I plant Sunchoke in Coal County, OK?

Coal County is in Zone 7b with an average last frost of March 28. Plan your Sunchoke planting based on this frost date — see the calendar above for exact timing.

What planting zone is Coal County, OK?

Coal County, Oklahoma is in USDA Hardiness Zone 7b. The average last spring frost is March 28 and first fall frost is November 2.

🌱

Your Coal County Garden Planner — Free

A 22-page printable planner built for Coal County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Coal County, OK. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.