Blog

When to Plant Shallot in San Juan County, NM

San Juan County, New Mexico Zone 5b April

San Juan County, New Mexico gardeners: here's your April plan

Here's what deserves your attention in San Juan County, New Mexico this month. Everything below is tailored to Zone 5b and timed around your local frost dates.

Avg. last frost May 12
Avg. first frost October 6
Soil temp (4") 20°F
Watering Critical
Pest pressure Low
Daylight 12.9 hrs
  1. Put shallot seeds straight in the ground

    Rake a smooth bed, make a shallow furrow, drop seeds at the spacing on the packet, water gently, walk away.

Get ahead of May
  • Transplants going out: shallot

Instant PDF download. No spam, unsubscribe any time.

Shallots are a gourmet allium prized for their complex, sweet, and mild flavor. Each bulb multiplies into a cluster, making them easy and rewarding to grow.

San Juan County, New Mexico is in USDA Zone 5b. The average last spring frost is May 12 and the first fall frost is October 6, giving you a growing season of approximately 147 days.

At an elevation of 8,301 feet, San Juan County receives approximately 14.3 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 87°F, providing good warmth for Shallot during the growing season. Sandy soil warms quickly in spring — great for early planting — but Shallot will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Shallot successfully. Mulch heavily to conserve soil moisture.

San Juan County, NM (Zone 5b) Short season
147 days
Last Spring Frost May 12
147 growing days
First Fall Frost October 6
Share this guide:

San Juan County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.3-8.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (4 days to spare)
Start indoors: Mar 31 Transplant: May 5 🍅 Harvest: Aug 4 – Sep 22
Recommended (50%) ✓ Fits season (7 days to spare)
Start indoors: Apr 7 Transplant: May 12 🍅 Harvest: Aug 11 – Sep 29
Safe Start (90%) ✓ Fits season (1 days to spare)
Start indoors: Apr 28 Transplant: Jun 2 🍅 Harvest: Sep 1 – Oct 20

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 Juan County

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

Soil pH

Your soil pH (7.3–8.5) is more alkaline than Shallot prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Drainage

Drainage is adequate for Shallot.

Organic Matter

Organic matter is low (0.9%). Add 2-3 inches of compost before planting Shallot.

How to Plant Shallot

1"
Planting Depth
6"
Between Plants
12"
Between Rows

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

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 1,400 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Shallot

Shallot needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Shallot Needs Rainfall You Supplement Action
Jan 1.1" 0" ❄️ Dormant
Feb 0.8" 0" ❄️ Dormant
Mar 0.8" 0" ❄️ Dormant
Apr 0.5" 0" ❄️ Dormant
May 4.3" 0.3" 4" 🚿 Regular watering
Jun 4.3" 0.5" 3.8" 🚿 Regular watering
Jul 4.3" 2.5" 1.8" 💧 Light watering
Aug 4.3" 2.6" 1.7" 💧 Light watering
Sep 4.3" 2.2" 2.1" 💧 Light watering
Oct 4.3" 1.3" 3" 🚿 Regular watering
Nov 0.8" 0" ❄️ Dormant
Dec 0.9" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in San Juan County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Shallot 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.

Shallot needs ~1,601 GDD — county provides 2,241 GDD Excellent fit

Shallot Planting Timeline — San Juan County, NM

Shallot Planting Calendar

Activity When Date Range
Start Indoors April 7 Apr 7 – Apr 21
Transplant Outdoors May 12 May 12 – May 26
Direct Sow April 28 Apr 28 – May 19
Harvest August 11 Aug 11 – Sep 29
Fall Sowing July 28 Jul 28 – Aug 11

Plant 1" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Start Indoors Direct Sow
May Transplant Outdoors Direct Sow
June
July Fall Sowing
August Fall Sowing Harvest
September Harvest
October
November
December
Share this guide:

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 2-3 times/week

📅 Days to Maturity

90–120 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 5b

📆 Growing Season

147 days in San Juan County

Growing Tips for Shallot in San Juan County

Direct sow Shallot outdoors after May 12 in San Juan County when soil has warmed and frost danger has passed.

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

Common pests for Shallot in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.

San Juan County receives only 14" of rain annually. Shallot needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Plant sets in fall for spring harvest or early spring for summer harvest. Mulch heavily if overwintering. Harvest when tops brown and dry, then cure for storage.

Companion Planting

Good Companions

Avoid Planting Near

  • Peas
  • Green Beans

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Shallot in San Juan County, NM?

San Juan County is in Zone 5b with an average last frost of May 12. Plan your Shallot planting based on this frost date — see the calendar above for exact timing.

What planting zone is San Juan County, NM?

San Juan County, New Mexico is in USDA Hardiness Zone 5b. The average last spring frost is May 12 and first fall frost is October 6.

🌱

Your San Juan County Garden Planner — Free

A 24-page printable planner built for San Juan County (Zone 5b). 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 Juan County, NM. Local conditions may vary. Last updated: April 2026.

Sources & credits

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