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When to Plant Radish in San Miguel County, NM

San Miguel County, New Mexico Zone 6b May

Your May planting checklist for San Miguel County, New Mexico

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. Harvest radish as they ripen

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

Looking ahead to June
  • First harvests: radish

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Radishes are one of the fastest-growing vegetables, with some varieties ready in under a month. They come in round, elongated, and large winter types.

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 Radish to ensure they mature before fall. Sandy soil warms quickly in spring — great for early planting — but Radish will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Radish 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
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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 (100 days to spare)
Transplant: May 1 🍅 Harvest: May 29 – Jun 19
Recommended (50%) ✓ Fits season (101 days to spare)
Transplant: May 10 🍅 Harvest: Jun 7 – Jun 28
Safe Start (90%) ✓ Fits season (96 days to spare)
Transplant: May 27 🍅 Harvest: Jun 24 – Jul 15

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 Radish's growing requirements.

Soil pH

Your soil pH (7.2–8.5) is more alkaline than Radish 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. Radish will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Radish.

Organic Matter

Organic matter is low (0.8%). Add 2-3 inches of compost before planting Radish.

How to Plant Radish

0.5"
Planting Depth
2"
Between Plants
6"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Radish

8
successive plantings in your 150-day season

Sow every 2.4 weeks. Last sowing by Sep 02 to harvest before frost.

For a dedicated fall crop, sow by Jul 29.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.4″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 395 gal / 100 sq ft
Drought risk

Water stress score is 10/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Radish

Radish needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Radish 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 2.2" 0.4" 1.8" 🚿 Regular watering
Jun 2.2" 0.5" 1.7" 🚿 Regular watering
Jul 2.2" 2.5" 0" ✅ Rainfall sufficient
Aug 2.2" 2.7" 0" ✅ Rainfall sufficient
Sep 2.2" 1.8" 0.4" 💧 Light watering
Oct 2.2" 1.3" 0.9" 💧 Light 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.

Radish 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.

Radish needs ~370 GDD — county provides 1,950 GDD Excellent fit

Radish Planting Timeline — San Miguel County, NM

Radish Planting Calendar

Activity When Date Range
Direct Sow April 26 Apr 26 – May 17
Harvest May 24 May 24 – Jun 14
Fall Sowing July 29 Jul 29 – Aug 12

Plant 0.5" deep · 2" apart · Rows 6" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Direct Sow
May Direct Sow Harvest
June Harvest
July Fall Sowing
August Fall Sowing
September
October
November
December
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Only during dry spells

📅 Days to Maturity

22–35 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 Radish in San Miguel County

Direct sow Radish 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 Radish with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

Your generous 150.0-day season in San Miguel County allows multiple plantings of Radish. Sow every 11.0 days for continuous harvest.

Common pests for Radish in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow every 1-2 weeks for continuous harvest. Do not transplant. Harvest spring radishes promptly to prevent them from becoming pithy and hot.

Companion Planting

Good Companions

Avoid Planting Near

  • Hyssop

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Radish in San Miguel County, NM?

San Miguel County is in Zone 6b with an average last frost of May 10. Plan your Radish 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.

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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 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.