Blog

When to Plant Comfrey in San Miguel County, NM

San Miguel County, New Mexico Zone 6b May

Top priorities for San Miguel County, New Mexico gardeners in May

Welcome to May in Zone 6b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost May 10
Avg. first frost October 7
Soil temp (4") 39°F
Watering Critical
Pest pressure Low
Daylight 13.9 hrs
  1. Move comfrey into the garden

    Frost risk is low now in San Miguel County, New Mexico. If you've been covering beds overnight, you can stop.

Instant PDF download. No spam, unsubscribe any time.

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

San Miguel County, New Mexico is in USDA Zone 6b. The average last spring frost is May 10 and the first fall frost is October 7, giving you a growing season of approximately 150 days.

At an elevation of 7,435 feet, San Miguel County receives approximately 14.4 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 84°F, so choose short-season varieties of Comfrey to ensure they mature before fall. Sandy soil warms quickly in spring — great for early planting — 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.

San Miguel County, NM (Zone 6b) Moderate season
150 days
Last Spring Frost May 10
150 growing days
First Fall Frost October 7
Share this guide:

San Miguel County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.2-8.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (9 days to spare)
Transplant: May 8 🍅 Harvest: Jul 10 – Sep 18
Recommended (50%) ✓ Fits season (10 days to spare)
Transplant: May 17 🍅 Harvest: Jul 19 – Sep 27
Safe Start (90%) ✓ Fits season (5 days to spare)
Transplant: Jun 3 🍅 Harvest: Aug 5 – Oct 14

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 San Miguel County

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

Soil pH

Your soil pH (7.2–8.5) is more alkaline than Comfrey prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in San Miguel 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

2
successive plantings in your 150-day season

Sow every 6.9 weeks. Last sowing by Jul 09 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 1,437 gal / 100 sq ft
Drought risk

Water stress score is 10/10 — 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 1.1" 0" ❄️ Dormant
Feb 0.9" 0" ❄️ Dormant
Mar 0.8" 0" ❄️ Dormant
Apr 0.5" 0" ❄️ Dormant
May 4.3" 0.4" 3.9" 🚿 Regular watering
Jun 4.3" 0.5" 3.8" 🚿 Regular watering
Jul 4.3" 2.5" 1.8" 💧 Light watering
Aug 4.3" 2.7" 1.6" 💧 Light watering
Sep 4.3" 1.8" 2.5" 🚿 Regular watering
Oct 4.3" 1.3" 3" 🚿 Regular watering
Nov 0.9" 0" ❄️ Dormant
Dec 1.1" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in San Miguel 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 ~975 GDD — county provides 1,950 GDD Excellent fit

Comfrey Planting Timeline — San Miguel County, NM

Comfrey Planting Calendar

Activity When Date Range
Transplant Outdoors May 17 May 17 – May 31
Harvest July 19 Jul 19 – Sep 27

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
Share this guide:

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · 2-3 times/week

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 6b

📆 Growing Season

150 days in San Miguel County

Growing Tips for Comfrey in San Miguel County

Direct sow Comfrey outdoors after May 10 in San Miguel County when soil has warmed and frost danger has passed.

Sandy soil in San Miguel County dries quickly — mulch Comfrey with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

San Miguel County receives only 14" of rain annually. Comfrey needs consistent moisture — 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 San Miguel County, NM?

San Miguel County is in Zone 6b with an average last frost of May 10. Plan your Comfrey planting based on this frost date — see the calendar above for exact timing.

What planting zone is San Miguel County, NM?

San Miguel County, New Mexico is in USDA Hardiness Zone 6b. The average last spring frost is May 10 and first fall frost is October 7.

🌱

Your San Miguel County Garden Planner — Free

A 24-page printable planner built for San Miguel 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.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for San Miguel County, NM. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.