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When to plant Comfrey in Knox County County,

Knox County County's 183-day season only supports one Comfrey planting per year. Sow between April 24 and May 8 for the best chance at full maturity before October 17.

When to Plant Comfrey in Knox County, MO

Comfrey is a vigorous perennial herb valued as a dynamic accumulator of nutrients. Its leaves make excellent mulch, compost activator, and liquid fertilizer.

Knox County, Missouri is in USDA Zone 6a. The average last spring frost is April 17 and the first fall frost is October 17, giving you a growing season of approximately 183 days.

At an elevation of 997 feet, Knox County receives approximately 39.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Comfrey to ensure they mature before fall.

Knox County, MO (Zone 6a) Moderate season
183 days
Last Spring Frost April 17
183 growing days
First Fall Frost October 17
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Knox County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Comfrey Planting Timeline — Knox County, MO

Comfrey Planting Calendar

Activity When Date Range
Transplant Outdoors April 24 Apr 24 – May 8
Harvest June 26 Jun 26 – Sep 4

Plant 0.5" deep · 8" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Transplant Outdoors
May Transplant Outdoors
June Harvest
July Harvest
August Harvest
September Harvest
October
November
December
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Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 6a

📆 Growing Season

183 days in Knox County

Growing Tips for Knox County

Plant root cuttings 2 inches deep. Choose Bocking 14 variety to prevent self-seeding. Cut leaves 3-4 times per season for mulch or compost. Avoid planting near pathways as it spreads.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Comfrey in Knox County, MO?

Knox County is in Zone 6a with an average last frost of April 17. Plan your Comfrey planting based on this frost date — see the calendar above for exact timing.

What planting zone is Knox County, MO?

Knox County, Missouri is in USDA Hardiness Zone 6a. The average last spring frost is April 17 and first fall frost is October 17.

When should I plant Comfrey in Knox County County, ?

In Knox County County, , plant Comfrey after the last frost (around April 17) and before the first frost (around October 17). Best results when soil holds above 50°F.

What growing zone is Knox County County, for Comfrey?

Knox County County sits in USDA Zone 6a. Comfrey grows reliably in zones 3a through 9b, so it's a good fit here.

Can Comfrey grow in Knox County County's climate?

Yes — Comfrey grows well in Knox County County's temperate climate. Knox County County averages a 183-day frost-free season, with last frost around April 17 and first frost around October 17.

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Your Knox County Garden Planner — Free

A 22-page printable planner built for Knox County (Zone 6a). 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 Knox County, MO. Local conditions may vary. Last updated: June 2026.

Sources & credits

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