Blog

When to Plant Comfrey in Mendocino County, CA

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

Mendocino County, California is in USDA Zone 8b. The average last spring frost is March 23 and the first fall frost is November 9, giving you a growing season of approximately 231 days.

At an elevation of 180 feet, Mendocino County receives approximately 24 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 87Β°F, providing good warmth for Comfrey during the growing season. Sandy soil warms quickly in spring β€” great for early planting β€” but Comfrey will need more frequent watering and organic matter to retain nutrients.

Mendocino County, CA (Zone 8b) Long season
231 days
Last Spring Frost March 23
231 growing days
First Fall Frost November 9

Mendocino County Soil Profile

Soil Type

Sandy Loam

Soil pH

6.1-7.2

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 β€” 5.2" 0" ❄️ Dormant
Feb β€” 4.6" 0" ❄️ Dormant
Mar 4.3" 3.7" 0.6" πŸ’§ Light watering
Apr 4.3" 1.9" 2.4" 🚿 Regular watering
May 4.3" 0.6" 3.7" 🚿 Regular watering
Jun 4.3" 0.2" 4.1" 🚿 Regular watering
Jul 4.3" 0" 4.3" 🚿 Regular watering
Aug 4.3" 0" 4.3" 🚿 Regular watering
Sep 4.3" 0.2" 4.1" 🚿 Regular watering
Oct 4.3" 1" 3.3" 🚿 Regular watering
Nov 4.3" 2.6" 1.7" πŸ’§ Light watering
Dec β€” 3.9" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Mendocino County). Supplement amounts are based on average rainfall β€” actual needs vary with temperature, soil, and mulching.

Comfrey Planting Timeline β€” Mendocino County, CA

Comfrey Planting Calendar

Activity When Date Range
Transplant Outdoors March 30 Mar 30 – Apr 13
Harvest June 1 Jun 1 – Aug 10

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

Month-by-Month Timeline

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

Growing Conditions

β˜€οΈ Sun

Partial Shade (3-6 hours)

πŸ’§ Water

Moderate β€” regular watering

πŸ“… Days to Maturity

60–90 days

πŸ§ͺ Soil pH

Needs 6–7 Β· Your soil: N/A

πŸ—ΊοΈ USDA Zone

Zone 8b

πŸ“† Growing Season

231 days in Mendocino County

Growing Tips for Mendocino 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 Mendocino County, CA?

Mendocino County is in Zone 8b with an average last frost of March 23. Plan your Comfrey planting based on this frost date β€” see the calendar above for exact timing.

What planting zone is Mendocino County, CA?

Mendocino County, California is in USDA Hardiness Zone 8b. The average last spring frost is March 23 and first fall frost is November 9.

🌱

Plan Your Garden with Confidence

Get our free Garden Planner β€” designed to help Mendocino County gardeners in Zone 8b organize planting dates, track what's growing, and never miss a planting window.

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. Frost dates are based on 50% probability averages for Mendocino County, CA. Local conditions may vary. Last updated: April 2026.