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When to Plant Lettuce in Mohave County, AZ

Mohave County, Arizona Zone 9b May

May to-do list for Mohave County, Arizona

Welcome to May in Zone 9b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost April 5
Avg. first frost November 8
Soil temp (4") 64°F
Watering Critical
Pest pressure High
Daylight 13.9 hrs
  1. Start lettuce indoors

    Your window is short. These crops want several weeks of indoor growth before they go outside.

  2. Collect lettuce at their peak

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

Before June arrives, get these ready
  • First harvests: lettuce

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Lettuce is a fast-growing cool-season green available in leaf, romaine, butterhead, and crisphead types. It is the foundation of salads and one of the easiest crops to grow.

Mohave County, Arizona is in USDA Zone 9b. The average last spring frost is April 5 and the first fall frost is November 8, giving you a growing season of approximately 217 days.

At an elevation of 3,748 feet, Mohave County receives approximately 8.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 96°F, so Lettuce may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Lettuce will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Lettuce successfully. Mulch heavily to conserve soil moisture.

Mohave County, AZ (Zone 9b) Long season
217 days
Last Spring Frost April 5
217 growing days
First Fall Frost November 8

Mohave County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.2-8.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (121 days to spare)
Start indoors: Feb 23 Transplant: Mar 23 🍅 Harvest: Apr 27 – Jul 6
Recommended (50%) ✓ Fits season (112 days to spare)
Start indoors: Mar 8 Transplant: Apr 5 🍅 Harvest: May 10 – Jul 19
Safe Start (90%) ✓ Fits season (113 days to spare)
Start indoors: Mar 20 Transplant: Apr 17 🍅 Harvest: May 22 – Jul 31

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 Mohave County

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

Soil pH

Your soil pH (7.2–8.4) is more alkaline than Lettuce prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Drainage

Drainage is adequate for Lettuce.

Organic Matter

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

How to Plant Lettuce

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Lettuce

8
successive plantings in your 217-day season

Sow every 3.4 weeks. Last sowing by Sep 09 to harvest before frost.

For a dedicated fall crop, sow by Sep 13.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.2″/week
You supply
0.9″/week
Watering frequency 2-3 times/week
Season total 1,741 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Lettuce

Lettuce needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Lettuce Needs Rainfall You Supplement Action
Jan 0.6" 0" ❄️ Dormant
Feb 0.4" 0" ❄️ Dormant
Mar 0.4" 0" ❄️ Dormant
Apr 3" 0.3" 2.7" 🚿 Regular watering
May 3" 0.2" 2.8" 🚿 Regular watering
Jun 3" 0.3" 2.7" 🚿 Regular watering
Jul 3" 1.5" 1.5" 🚿 Regular watering
Aug 3" 1.6" 1.4" 💧 Light watering
Sep 3" 1" 2" 🚿 Regular watering
Oct 3" 0.8" 2.2" 🚿 Regular watering
Nov 3" 0.4" 2.6" 🚿 Regular watering
Dec 0.6" 0" ❄️ Dormant

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

Lettuce 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.

Lettuce needs ~990 GDD — county provides 4,774 GDD Excellent fit

Lettuce Planting Timeline — Mohave County, AZ

Lettuce Planting Calendar

Activity When Date Range
Start Indoors March 8 Mar 8 – Mar 22
Transplant Outdoors April 5 Apr 5 – Apr 19
Direct Sow March 15 Mar 15 – Apr 5
Harvest May 10 May 10 – Jul 19
Fall Sowing September 13 Sep 13 – Sep 27

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.7"/week · 2-3 times/week

📅 Days to Maturity

30–60 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 9b

📆 Growing Season

217 days in Mohave County

Growing Tips for Lettuce in Mohave County

Direct sow Lettuce outdoors after April 05 in Mohave County when soil has warmed and frost danger has passed.

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

Summer highs in Mohave County reach 96°F — grow Lettuce as a spring or fall crop. Use shade cloth if planting in summer.

Your generous 217.0-day season in Mohave County allows multiple plantings of Lettuce. Sow every 15.0 days for continuous harvest.

Common pests for Lettuce in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

Sow seeds directly every 2 weeks for continuous harvest. Provide afternoon shade in warm weather to delay bolting. Harvest in the morning for crispest leaves.

Recommended Lettuce Varieties for Mohave County

Bolt-resistant varieties for warm summers — grow as spring/fall crop

Jericho Muir Nevada New Red Fire

Companion Planting

Good Companions

Avoid Planting Near

  • Celery

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Lettuce Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Let plants bolt and flower. Harvest seed heads when fluffy.
Storage Store airtight; viable 6 years at 35°F, under 45% humidity.

Very easy to save. Let a few plants bolt each season.

Frequently Asked Questions

When should I plant Lettuce in Mohave County, AZ?

Mohave County is in Zone 9b with an average last frost of April 5. Plan your Lettuce planting based on this frost date — see the calendar above for exact timing.

What planting zone is Mohave County, AZ?

Mohave County, Arizona is in USDA Hardiness Zone 9b. The average last spring frost is April 5 and first fall frost is November 8.

🌱

Your Mohave County Garden Planner — Free

A 24-page printable planner built for Mohave County (Zone 9b). 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 Mohave County, AZ. 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.