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When to Plant Lettuce in Los Angeles County, CA

Los Angeles County, California Zone 10b May

May in the garden — Los Angeles County, California

Here's what deserves your attention in Los Angeles County, California this month. Everything below is tailored to Zone 10b and timed around your local frost dates.

Avg. last frost April 3
Avg. first frost November 21
Soil temp (4") 80°F
Watering Critical
Pest pressure High
Daylight 13.8 hrs
  1. Get lettuce seeds going inside

    Label every cell. You will absolutely forget which is which otherwise.

  2. Start harvesting lettuce

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

Coming up in June — start thinking about
  • 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.

Los Angeles County, California is in USDA Zone 10b. The average last spring frost is April 3 and the first fall frost is November 21, giving you a growing season of approximately 232 days.

At an elevation of 1,315 feet, Los Angeles County receives approximately 12.9 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Lettuce during the growing season. With low rainfall, drip irrigation is essential for growing Lettuce successfully. Mulch heavily to conserve soil moisture.

Los Angeles County, CA (Zone 10b) Long season
232 days
Last Spring Frost April 3
232 growing days
First Fall Frost November 21

Los Angeles County Soil Profile

Soil Type

Loam

Soil pH

5.8-7.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (143 days to spare)
Start indoors: Feb 6 Transplant: Mar 6 🍅 Harvest: Apr 10 – Jun 19
Recommended (50%) ✓ Fits season (127 days to spare)
Start indoors: Mar 6 Transplant: Apr 3 🍅 Harvest: May 8 – Jul 17
Safe Start (90%) ✓ Fits season (91 days to spare)
Start indoors: Apr 30 Transplant: May 28 🍅 Harvest: Jul 2 – Sep 10

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 Los Angeles County

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

Soil pH

Your soil pH (5.8–7.5) overlaps with Lettuce's range (6.0–7.0), though not a perfect match.

Soil Texture

The loam soil in Los Angeles County is excellent for Lettuce — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.1%). Annual compost additions will help 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

9
successive plantings in your 232-day season

Sow every 3.4 weeks. Last sowing by Sep 22 to harvest before frost.

For a dedicated fall crop, sow by Sep 26.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.2″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 1,156 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 2.4" 0" ❄️ Dormant
Feb 2.5" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 3" 1.2" 1.8" 🚿 Regular watering
May 3" 0.4" 2.6" 🚿 Regular watering
Jun 3" 0.1" 2.9" 🚿 Regular watering
Jul 3" 0" 3" 🚿 Regular watering
Aug 3" 0" 3" 🚿 Regular watering
Sep 3" 0.2" 2.8" 🚿 Regular watering
Oct 3" 0.6" 2.4" 🚿 Regular watering
Nov 3" 1.3" 1.7" 🚿 Regular watering
Dec 2.1" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Nov in Los Angeles 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 ~686 GDD — county provides 3,538 GDD Excellent fit

Lettuce Planting Timeline — Los Angeles County, CA

Lettuce Planting Calendar

Activity When Date Range
Start Indoors March 6 Mar 6 – Mar 20
Transplant Outdoors April 3 Apr 3 – Apr 17
Direct Sow March 13 Mar 13 – Apr 3
Harvest May 8 May 8 – Jul 17
Fall Sowing September 26 Sep 26 – Oct 10

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 Fall Sowing
November
December

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.7"/week · 1-2 times/week

📅 Days to Maturity

30–60 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 10b

📆 Growing Season

232 days in Los Angeles County

Growing Tips for Lettuce in Los Angeles County

Direct sow Lettuce outdoors after April 03 in Los Angeles County when soil has warmed and frost danger has passed.

Your generous 232.0-day season in Los Angeles 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 Los Angeles 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 Los Angeles County, CA?

Los Angeles County is in Zone 10b with an average last frost of April 3. Plan your Lettuce planting based on this frost date — see the calendar above for exact timing.

What planting zone is Los Angeles County, CA?

Los Angeles County, California is in USDA Hardiness Zone 10b. The average last spring frost is April 3 and first fall frost is November 21.

🌱

Your Los Angeles County Garden Planner — Free

A 24-page printable planner built for Los Angeles County (Zone 10b). 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 Los Angeles County, CA. 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.