Blog

When to Plant Comfrey in USDA Zone 6b

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

In Zone 6b, the average last spring frost is around April 3 and the first fall frost is around October 25, giving you a growing season of approximately 205 days.

Zone 6b Long season
205 days
Last Spring Frost April 3
205 growing days
First Fall Frost October 25

Comfrey Planting Timeline — Zone 6b

Where Is USDA Zone 6b?

The map below highlights the states that contain Zone 6b. Click any state to see the Comfrey planting schedule for that location.

Prints a clean, ink-friendly version without maps or navigation.

Comfrey Planting Calendar — Zone 6b

Activity When Date Range
Transplant Outdoors April 10 Apr 10 – Apr 24
Harvest June 12 Jun 12 – Aug 21

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

Month-by-Month Timeline

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

Free Zone 6b Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 6b with start dates, transplant windows, and harvest times.

Get My Free Calendar →

Growing Conditions

Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

Days to Maturity

60–90 days

Soil pH

6 – 7

Zone Temperature Range

-5°F to 0°F average annual minimum

Growing Season

205 days (Zone 6b average)

Planting Specifications

Planting Depth0.5 inches
Plant Spacing8 inches apart
Row Spacing12 inches between rows

Succession Planting Comfrey in Zone 6b

4
successive plantings in Zone 6b's ~205-day season

Sow every 6.9 weeks for continuous harvest throughout the season.

Growing Tips for Comfrey in Zone 6b

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

Saving Comfrey Seeds

Recommended for Your Garden

🪴
Fabric Grow Bags $10-25

Breathable fabric pots that promote healthy root growth and prevent overwatering.

🏺
Self-Watering Planters $15-40

Built-in reservoir keeps herbs and greens consistently watered with less effort.

🌱
Seed Starting Trays $8-20

Start seeds indoors with reusable cell trays and humidity domes.

Related Plants

Frequently Asked Questions

When should I plant Comfrey in Zone 6b?

In Zone 6b, plan your Comfrey planting around the average last frost date of April 3. Transplant seedlings around April 10.

Can Comfrey grow in Zone 6b?

Yes, Comfrey can grow well in Zone 6b, hardy in USDA zones 3a through 9b. Zone 6b has a growing season of approximately 205 days, which is sufficient for Comfrey (60-90 days to maturity).

When can I harvest Comfrey in Zone 6b?

In Zone 6b, expect to harvest Comfrey from June 12 – August 21. Comfrey takes 60-90 days from planting to harvest.

What is the last frost date for Zone 6b?

The average last spring frost in Zone 6b is around April 3, and the first fall frost is around October 25. This gives a growing season of approximately 205 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Comfrey?

Good companion plants for Comfrey include Fruit Trees, Tomatoes, Peppers. These companions can help with pest control, pollination, and nutrient sharing.

🌱

Plan Your Garden with Confidence

Get our free Garden Planner — organize your planting dates for Zone 6b, track your crops, and plan your garden season from seed to harvest.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Planting dates are estimates based on average frost dates — local conditions may vary. Last updated: April 2026.