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When to plant Comfrey in Leelanau County, MI

In Leelanau County, Comfrey is a spring-only crop. Plant May 12–May 26 once soil hits 50°F.

When to Plant Comfrey in Leelanau County, MI

Leelanau County, Michigan Zone 6b June

Your June planting checklist for Leelanau County, Michigan

Here's what deserves your attention in Leelanau County, Michigan this month. Everything below is tailored to Zone 6b and timed around your local frost dates.

Avg. last frost May 5
Avg. first frost October 22
Soil temp (4") 67°F
Watering Low
Pest pressure High
Daylight 15.4 hrs
Before July arrives, get these ready
  • First harvests: comfrey

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

Leelanau County, Michigan is in USDA Zone 6b. The average last spring frost is May 5 and the first fall frost is October 22, giving you a growing season of approximately 170 days.

At an elevation of 1,223 feet, Leelanau County receives approximately 41.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Comfrey during the growing season.

Leelanau County, MI (Zone 6b) Moderate season
170 days
Last Spring Frost May 5
170 growing days
First Fall Frost October 22

Leelanau County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-7.1

Drainage

Well Drained

Comfrey Planting Risk Windows

Early Start (70% safe) ✓ Fits season (27 days to spare)
Transplant: May 4 🍅 Harvest: Jul 6 – Sep 14
Recommended (50%) ✓ Fits season (30 days to spare)
Transplant: May 12 🍅 Harvest: Jul 14 – Sep 22
Safe Start (90%) ✓ Fits season (32 days to spare)
Transplant: May 28 🍅 Harvest: Jul 30 – Oct 8

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.

Soil Compatibility in Leelanau County

How your county's soil matches Comfrey's growing requirements.

Soil pH

Your soil pH (5.8–7.1) overlaps with Comfrey's range (6.0–7.0), though not a perfect match.

Soil Texture

The silt loam soil in Leelanau County is excellent for Comfrey — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Comfrey.

Organic Matter

Organic matter is excellent (4.2%) — Comfrey will thrive.

How to Plant Comfrey

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Succession Planting Comfrey

3
successive plantings in your 170-day season

Sow every 6.9 weeks. Last sowing by Jul 24 to harvest before frost.

Comfrey Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 416 gal / 100 sq ft

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 1.6" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 3.2" 0" ❄️ Dormant
Apr 3.6" 0" ❄️ Dormant
May 4.3" 5.3" 0" ✅ Rainfall sufficient
Jun 4.3" 4.7" 0" ✅ Rainfall sufficient
Jul 4.3" 4.6" 0" ✅ Rainfall sufficient
Aug 4.3" 5" 0" ✅ Rainfall sufficient
Sep 4.3" 4" 0.3" 💧 Light watering
Oct 4.3" 2.9" 1.4" 💧 Light watering
Nov 2.7" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

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

Comfrey Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Comfrey needs ~1,200 GDD — county provides 2,720 GDD Excellent fit

Comfrey Planting Timeline — Leelanau County, MI

Comfrey Planting Calendar

Activity When Date Range
Transplant Outdoors May 12 May 12 – May 26
Harvest July 14 Jul 14 – Sep 22

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

1"/week · Only during dry spells

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6b

📆 Growing Season

170 days in Leelanau County

Growing Tips for Comfrey in Leelanau County

Direct sow Comfrey outdoors after May 05 in Leelanau County when soil has warmed and frost danger has passed.

General growing tips

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 Leelanau County, MI?

Leelanau County is in Zone 6b with an average last frost of May 5. Plan your Comfrey planting based on this frost date — see the calendar above for exact timing.

What planting zone is Leelanau County, MI?

Leelanau County, Michigan is in USDA Hardiness Zone 6b. The average last spring frost is May 5 and first fall frost is October 22.

When should I plant Comfrey in Leelanau County, MI?

In Leelanau County, MI, plant Comfrey after the last frost (around May 5) and before the first frost (around October 22). Best results when soil holds above 50°F.

What growing zone is Leelanau County, MI for Comfrey?

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

Can Comfrey grow in Leelanau County's climate?

Yes — Comfrey grows well in Leelanau County's temperate climate. Leelanau County averages a 170-day frost-free season, with last frost around May 5 and first frost around October 22.

🌱

Your Leelanau County Garden Planner — Free

A 22-page printable planner built for Leelanau County (Zone 6b). 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 Leelanau County, MI. 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.