Blog

When to Plant Leeks in Dona Ana County, NM

Dona Ana County, New Mexico Zone 8b May

May to-do list for Dona Ana County, New Mexico

We've pulled the most time-sensitive tasks for Dona Ana County, New Mexico this May and put them front and centre. Tackle them in order.

Avg. last frost March 30
Avg. first frost October 30
Soil temp (4") 59°F
Watering Critical
Pest pressure High
Daylight 13.7 hrs
  1. Get leeks seeds going inside

    Starting these indoors now means sturdy transplants ready the moment your soil warms up.

A few tasks this May that'll pay off in June
  • First harvests: leeks

Instant PDF download. No spam, unsubscribe any time.

Leeks are a mild, sweet allium that produces long white shanks. They are more refined than onions and are a key ingredient in soups, stews, and gratins.

Dona Ana County, New Mexico is in USDA Zone 8b. The average last spring frost is March 30 and the first fall frost is October 30, giving you a growing season of approximately 214 days.

At an elevation of 4,516 feet, Dona Ana County receives approximately 14.1 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 96°F, so Leeks may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Leeks will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Leeks successfully. Mulch heavily to conserve soil moisture.

Dona Ana County, NM (Zone 8b) Long season
214 days
Last Spring Frost March 30
214 growing days
First Fall Frost October 30

Dona Ana County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.3-8.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (63 days to spare)
Start indoors: Jan 29 Transplant: Mar 5 🍅 Harvest: Jun 4 – Aug 20
Recommended (50%) ✓ Fits season (46 days to spare)
Start indoors: Feb 23 Transplant: Mar 30 🍅 Harvest: Jun 29 – Sep 14
Safe Start (90%) ✓ Fits season (37 days to spare)
Start indoors: Mar 31 Transplant: May 5 🍅 Harvest: Aug 4 – 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 Dona Ana County

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

Soil pH

Your soil pH (7.3–8.9) is more alkaline than Leeks prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Drainage

Drainage is adequate for Leeks.

Organic Matter

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

How to Plant Leeks

1"
Planting Depth
15"
Between Plants
24"
Between Rows

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

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
0.3″/week
You supply
0.9″/week
Watering frequency 2-3 times/week
Season total 1,744 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Leeks

Leeks needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.

Month Leeks Needs Rainfall You Supplement Action
Jan 1.1" 0" ❄️ Dormant
Feb 0.9" 0" ❄️ Dormant
Mar 3.5" 0.8" 2.7" 🚿 Regular watering
Apr 3.5" 0.4" 3.1" 🚿 Regular watering
May 3.5" 0.3" 3.2" 🚿 Regular watering
Jun 3.5" 0.6" 2.9" 🚿 Regular watering
Jul 3.5" 2.6" 0.9" 💧 Light watering
Aug 3.5" 2.7" 0.8" 💧 Light watering
Sep 3.5" 1.7" 1.8" 🚿 Regular watering
Oct 3.5" 1.2" 2.3" 🚿 Regular watering
Nov 0.8" 0" ❄️ Dormant
Dec 1" 0" ❄️ Dormant

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

Leeks 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.

Leeks needs ~2,640 GDD — county provides 4,708 GDD Excellent fit

Leeks Planting Timeline — Dona Ana County, NM

Leeks Planting Calendar

Activity When Date Range
Start Indoors February 23 Feb 23 – Mar 9
Transplant Outdoors March 30 Mar 30 – Apr 13
Direct Sow March 16 Mar 16 – Apr 6
Harvest June 29 Jun 29 – Sep 14
Fall Sowing August 21 Aug 21 – Sep 4

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.8"/week · 2-3 times/week

📅 Days to Maturity

90–150 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 8b

📆 Growing Season

214 days in Dona Ana County

Growing Tips for Leeks in Dona Ana County

Direct sow Leeks outdoors after March 30 in Dona Ana County when soil has warmed and frost danger has passed.

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

With summer highs reaching 96°F in Dona Ana County, provide afternoon shade for Leeks and water deeply in the morning.

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

General growing tips

Start seeds indoors 10-12 weeks before last frost. Transplant into trenches and hill soil around stems as they grow to increase the white portion. Harvest as needed.

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 Leeks in Dona Ana County, NM?

Dona Ana County is in Zone 8b with an average last frost of March 30. Plan your Leeks planting based on this frost date — see the calendar above for exact timing.

What planting zone is Dona Ana County, NM?

Dona Ana County, New Mexico is in USDA Hardiness Zone 8b. The average last spring frost is March 30 and first fall frost is October 30.

🌱

Your Dona Ana County Garden Planner — Free

A 24-page printable planner built for Dona Ana County (Zone 8b). 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 Dona Ana 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.