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When to Plant Comfrey in Grant County, NM

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

Grant County, New Mexico is in USDA Zone 7a. The average last spring frost is April 27 and the first fall frost is October 22, giving you a growing season of approximately 178 days.

At an elevation of 3,721 feet, Grant County receives approximately 15.8 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 92ยฐF, providing good warmth for Comfrey during the growing season. 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. With low rainfall, drip irrigation is essential for growing Comfrey successfully. Mulch heavily to conserve soil moisture.

Grant County, NM (Zone 7a) Moderate season
178 days
Last Spring Frost April 27
178 growing days
First Fall Frost October 22

Grant County Soil Profile

Soil Type

Sandy Loam

Soil pH

6.9-8.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (41 days to spare)
Transplant: Apr 24 🍅 Harvest: Jun 26 – Sep 4
Recommended (50%) ✓ Fits season (38 days to spare)
Transplant: May 4 🍅 Harvest: Jul 6 – Sep 14
Safe Start (90%) ✓ Fits season (29 days to spare)
Transplant: May 29 🍅 Harvest: Jul 31 – Oct 9

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 Grant County

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

Soil pH

Your soil pH (6.9โ€“8.2) is more alkaline than Comfrey prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Grant 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 low (0.8%). Add 2-3 inches of compost before planting Comfrey.

How to Plant Comfrey

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

Succession Planting Comfrey

3
successive plantings in your 178-day season

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.4″/week
You supply
1.1″/week
Watering frequency 2-3 times/week
Season total 1,763 gal / 100 sq ft
Drought risk

Water stress score is 10/10 โ€” consider drought-tolerant varieties and mulching

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€” 1" 0" โ„๏ธ Dormant
Feb โ€” 0.9" 0" โ„๏ธ Dormant
Mar โ€” 0.8" 0" โ„๏ธ Dormant
Apr 4.3" 0.5" 3.8" ๐Ÿšฟ Regular watering
May 4.3" 0.3" 4" ๐Ÿšฟ Regular watering
Jun 4.3" 0.6" 3.7" ๐Ÿšฟ Regular watering
Jul 4.3" 2.8" 1.5" ๐Ÿ’ง Light watering
Aug 4.3" 2.8" 1.5" ๐Ÿ’ง Light watering
Sep 4.3" 2.4" 1.9" ๐Ÿ’ง Light watering
Oct 4.3" 1.6" 2.7" ๐Ÿšฟ Regular watering
Nov โ€” 0.9" 0" โ„๏ธ Dormant
Dec โ€” 1.1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Grant 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 ~1,425 GDD — county provides 3,382 GDD Excellent fit

Comfrey Planting Timeline โ€” Grant County, NM

Comfrey Planting Calendar

Activity When Date Range
Transplant Outdoors May 4 May 4 โ€“ May 18
Harvest July 6 Jul 6 โ€“ Sep 14

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 โ€”
July Harvest
August Harvest
September Harvest
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

60โ€“90 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

178 days in Grant County

Growing Tips for Comfrey in Grant County

Direct sow Comfrey outdoors after April 27 in Grant County when soil has warmed and frost danger has passed.

Sandy soil in Grant 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.

Grant County receives only 16" of rain annually. Comfrey needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

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 Grant County, NM?

Grant County is in Zone 7a with an average last frost of April 27. Plan your Comfrey planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Grant County, NM?

Grant County, New Mexico is in USDA Hardiness Zone 7a. The average last spring frost is April 27 and first fall frost is October 22.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Grant County gardeners in Zone 7a 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 Grant County, NM. Local conditions may vary. Last updated: April 2026.