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When to plant Sunchoke in Harrison County, MO

Plant Sunchoke in Harrison County during the brief May 3–May 17 window. With 179 frost-free days, fall plantings can't mature before October 15.

When to Plant Sunchoke in Harrison County, MO

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

Harrison County, Missouri is in USDA Zone 5b. The average last spring frost is April 19 and the first fall frost is October 15, giving you a growing season of approximately 179 days.

At an elevation of 1,349 feet, Harrison County receives approximately 37.7 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.

Harrison County, MO (Zone 5b) Moderate season
179 days
Last Spring Frost April 19
179 growing days
First Fall Frost October 15

Harrison County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Sunchoke Planting Timeline — Harrison County, MO

Sunchoke Planting Calendar

Activity When Date Range
Transplant Outdoors May 3 May 3 – May 17
Harvest August 23 Aug 23 – Oct 18

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

Month-by-Month Timeline

MonthActivities
January
February
March
April
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

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 5b

📆 Growing Season

179 days in Harrison County

Growing Tips for Harrison 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 Harrison County, MO?

Harrison County is in Zone 5b with an average last frost of April 19. Plan your Sunchoke planting based on this frost date — see the calendar above for exact timing.

What planting zone is Harrison County, MO?

Harrison County, Missouri is in USDA Hardiness Zone 5b. The average last spring frost is April 19 and first fall frost is October 15.

When should I plant Sunchoke in Harrison County, MO?

In Harrison County, MO, plant Sunchoke after the last frost (around April 19) and before the first frost (around October 15). Best results when soil holds above 50°F.

What growing zone is Harrison County, MO for Sunchoke?

Harrison County sits in USDA Zone 5b. Sunchoke grows reliably in zones 3a through 9b, so it's a good fit here.

Can Sunchoke grow in Harrison County's climate?

Yes — Sunchoke grows well in Harrison County's temperate climate. Harrison County averages a 179-day frost-free season, with last frost around April 19 and first frost around October 15.

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Your Harrison County Garden Planner — Free

A 22-page printable planner built for Harrison County (Zone 5b). 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 Harrison County, MO. Local conditions may vary. Last updated: August 2026.

Sources & credits

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