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When to Plant Comfrey in Mobile County, AL

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

Mobile County, Alabama is in USDA Zone 8b. The average last spring frost is March 3 and the first fall frost is November 24, giving you a growing season of approximately 266 days.

At an elevation of 101 feet, Mobile County receives approximately 48.3 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 97ยฐF, so Comfrey may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Comfrey will need more frequent watering and organic matter to retain nutrients.

Mobile County, AL (Zone 8b) Long season
266 days
Last Spring Frost March 3
266 growing days
First Fall Frost November 24

Mobile County Soil Profile

Soil Type

Sandy Loam

Soil pH

4.8-6.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (131 days to spare)
Transplant: Feb 26 🍅 Harvest: Apr 30 – Jul 9
Recommended (50%) ✓ Fits season (126 days to spare)
Transplant: Mar 10 🍅 Harvest: May 12 – Jul 21
Safe Start (90%) ✓ Fits season (126 days to spare)
Transplant: Mar 27 🍅 Harvest: May 29 – Aug 7

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 Mobile County

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

Soil pH

Your soil pH (4.8โ€“6.1) is more acidic than Comfrey prefers (6.0โ€“7.0). Add garden lime to raise pH.

Soil Texture

Sandy soil in Mobile County warms quickly in spring but drains fast. Comfrey will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Comfrey.

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Comfrey.

How to Plant Comfrey

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

Succession Planting Comfrey

5
successive plantings in your 266-day season

Sow every 6.9 weeks. Last sowing by Aug 26 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
Watering frequency Natural rainfall sufficient
Season total 0 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 โ€” 3.7" 0" โ„๏ธ Dormant
Feb โ€” 3.5" 0" โ„๏ธ Dormant
Mar 4.3" 4.9" 0" โœ… Rainfall sufficient
Apr 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
May 4.3" 3.5" 0.8" ๐Ÿ’ง Light watering
Jun 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Jul 4.3" 5.5" 0" โœ… Rainfall sufficient
Aug 4.3" 4.2" 0.1" ๐Ÿ’ง Light watering
Sep 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Oct 4.3" 3.5" 0.8" ๐Ÿ’ง Light watering
Nov 4.3" 4.3" 0" โœ… Rainfall sufficient
Dec โ€” 4" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Mobile County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 ~1,706 GDD — county provides 6,051 GDD Excellent fit

Comfrey Planting Timeline โ€” Mobile County, AL

Comfrey Planting Calendar

Activity When Date Range
Transplant Outdoors March 10 Mar 10 โ€“ Mar 24
Harvest May 12 May 12 โ€“ Jul 21

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

60โ€“90 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 8b

๐Ÿ“† Growing Season

266 days in Mobile County

Growing Tips for Comfrey in Mobile County

Direct sow Comfrey outdoors after March 03 in Mobile County when soil has warmed and frost danger has passed.

Sandy soil in Mobile County dries quickly โ€” mulch Comfrey with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 97ยฐF in Mobile County, provide afternoon shade for Comfrey and water deeply in the morning.

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 Mobile County, AL?

Mobile County is in Zone 8b with an average last frost of March 3. Plan your Comfrey planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Mobile County, AL?

Mobile County, Alabama is in USDA Hardiness Zone 8b. The average last spring frost is March 3 and first fall frost is November 24.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Mobile 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 Mobile County, AL. Local conditions may vary. Last updated: April 2026.