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When to Plant Comfrey in Lake of the Woods 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.

Lake of the Woods County, Minnesota is in USDA Zone 3a. The average last spring frost is May 19 and the first fall frost is September 22, giving you a growing season of approximately 126 days.

At an elevation of 1,032 feet, Lake of the Woods County receives approximately 32.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80ยฐF, so choose short-season varieties of Comfrey to ensure they mature before fall.

Lake of the Woods County, MN (Zone 3a) Short season
126 days
Last Spring Frost May 19
126 growing days
First Fall Frost September 22

Lake of the Woods County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: May 21 🍅 Harvest: Jul 23 – Sep 24
Recommended (50%) ✗ May not fit
Transplant: May 26 🍅 Harvest: Jul 28 – Sep 29
Safe Start (90%) ✗ May not fit
Transplant: Jun 10 🍅 Harvest: Aug 12 – Oct 14

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 228 gal / 100 sq ft
Comfrey needs ~750 GDD — county provides 1,260 GDD Excellent fit

Comfrey Planting Timeline โ€” Lake of the Woods County, MN

Comfrey Planting Calendar

Activity When Date Range
Transplant Outdoors May 26 May 26 โ€“ Jun 9
Harvest July 28 Jul 28 โ€“ Sep 29

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Partial Shade (3-6 hours)

Water

Moderate โ€” regular watering

Days to Maturity

60โ€“90 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 3a

Growing Season

126 days

Growing Tips for Lake of the Woods 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

Level Up Your Garden

Frequently Asked Questions

When should I plant Comfrey in Lake of the Woods County, MN?

Lake of the Woods County is in Zone 3a with an average last frost of May 19. Plan your Comfrey planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Lake of the Woods County, MN?

Lake of the Woods County, Minnesota is in USDA Hardiness Zone 3a. The average last spring frost is May 19 and first fall frost is September 22.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Lake of the Woods County gardeners in Zone 3a organize planting dates, track what's growing, and never miss a planting window.

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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 Lake of the Woods County, MN. Local conditions may vary. Last updated: April 2026.