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When to plant Comfrey in Stearns County County,

Stearns County County's short 156-day growing season means one Comfrey planting between May 10 and May 24. No fall crop in Zone 4b.

When to Plant Comfrey in Stearns County, MN

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

Stearns County, Minnesota is in USDA Zone 4b. The average last spring frost is May 3 and the first fall frost is October 6, giving you a growing season of approximately 156 days.

At an elevation of 772 feet, Stearns County receives approximately 37.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Comfrey to ensure they mature before fall.

Stearns County, MN (Zone 4b) Moderate season
156 days
Last Spring Frost May 3
156 growing days
First Fall Frost October 6

Stearns County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-6.7

Drainage

Well Drained

Monthly Watering Guide for Comfrey

Comfrey needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Comfrey Needs Rainfall You Supplement Action
Jan 1.5" 0" ❄️ Dormant
Feb 1.8" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 3.5" 0" ❄️ Dormant
May 4.3" 4.2" 0.1" 💧 Light watering
Jun 4.3" 5" 0" ✅ Rainfall sufficient
Jul 4.3" 3.9" 0.4" 💧 Light watering
Aug 4.3" 3.6" 0.7" 💧 Light watering
Sep 4.3" 3.9" 0.4" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 2.7" 0" ❄️ Dormant
Dec 2.5" 0" ❄️ Dormant

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

Comfrey Planting Timeline — Stearns County, MN

Comfrey Planting Calendar

Activity When Date Range
Transplant Outdoors May 10 May 10 – May 24
Harvest July 12 Jul 12 – Sep 20

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

Month-by-Month Timeline

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

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 4b

📆 Growing Season

156 days in Stearns County

Growing Tips for Stearns 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 Stearns County, MN?

Stearns County is in Zone 4b with an average last frost of May 3. Plan your Comfrey planting based on this frost date — see the calendar above for exact timing.

What planting zone is Stearns County, MN?

Stearns County, Minnesota is in USDA Hardiness Zone 4b. The average last spring frost is May 3 and first fall frost is October 6.

When should I plant Comfrey in Stearns County County, ?

In Stearns County County, , plant Comfrey after the last frost (around May 3) and before the first frost (around October 6). Best results when soil holds above 50°F.

What growing zone is Stearns County County, for Comfrey?

Stearns County County sits in USDA Zone 4b. Comfrey grows reliably in zones 3a through 9b, so it's a good fit here.

Can Comfrey grow in Stearns County County's climate?

Yes — Comfrey grows well in Stearns County County's temperate climate. Stearns County County averages a 156-day frost-free season, with last frost around May 3 and first frost around October 6.

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Your Stearns County Garden Planner — Free

A 22-page printable planner built for Stearns County (Zone 4b). 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 Stearns County, MN. Local conditions may vary. Last updated: June 2026.

Sources & credits

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