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When to Plant Lettuce in California

Published: April 21, 2026

Zone 9bWarm climateAlso Zones 6b, 7b, 10a, 10b
Fresh green lettuce heads in a garden bed

California gardeners in Zone 9b enjoy an extended 50-week growing season for lettuce. Cool-season crops like lettuce do best in fall, winter, and early spring in California — the hot summers bolt these plants before they can be harvested. This guide gives exact dates for California based on your local frost calendar.

Lettuce Planting Dates for California

Start seeds indoorsDecember 18–25
Last frost (average)January 15
Transplant outdoorsDecember 18–28
Direct sow outdoorsDecember 4–14
Expect first harvestJanuary 17 – February 16
Fall crop startNovember 19–29
Fall harvestDecember 19
First fall frost (average)December 31

Dates above assume Zone 9b, the most common zone in California. Gardeners in cooler Santa Rosa (Zone 6b) plant 1–2 weeks later; warmer San Francisco (Zone 10b) can plant 1–2 weeks earlier.

Growing Lettuce in California's Climate

California's warm Zone 9b climate makes lettuce a fall, winter, and early spring crop rather than a summer one. The cool-season window runs roughly October through April in California — plant outside this window and the lettuce will bolt (send up a flower stalk and turn bitter) before it produces a harvestable crop.

Succession planting stretches the lettuce harvest window. Sow small amounts every two weeks from October through February — you will have staggered harvests rather than a single wave to process all at once. Bolt-resistant varieties extend the usable window an extra three to four weeks into warming weather.

Common lettuce pests to watch for in California include Aphids and Slugs. The first line of defense is companion planting: Carrot and Radish planted nearby discourage several of these pests by confusing host-plant identification or repelling adults before they can lay eggs. Weekly garden walks in the early morning catch problems when they're still manageable.

Lettuce Garden Calendar for California

MonthTaskNotes
JanuaryHarden off seedlingsSet seedlings outdoors 1–2 hours daily, increasing gradually
FebruaryOff-season
MarchOff-season
AprilOff-season
MayWatch for boltingHarvest promptly; spring heat arrives quickly
JuneOff-season
JulyOff-season
AugustOff-season
SeptemberOff-season
OctoberOff-season
NovemberFall crop plantingTransplant or direct sow for fall harvest before frost
DecemberTransplant outdoorsSoil temp must be 40°F+; nighttime lows above 50°F

Lettuce Growing Tips for California Gardeners

  • Direct sow very shallowly — lettuce seeds need light to germinate; cover with just 1/8 inch of soil.
  • Cut outer leaves 1 inch above the crown for "cut-and-come-again" harvests lasting weeks.
  • California's cool-season lettuce plants best in October, November, and December for winter and early spring harvest. Spring plantings bolt before producing a harvestable crop.
  • Provide afternoon shade in warmer climates (Zones 7+) to extend the spring window before heat bolts plants.

Companion Planting for Lettuce in California

In California's warm climate, planting lettuce with Carrot and Radish helps deter pests and improve soil. Avoid planting near Fennel and Celery, which inhibit lettuce growth through root chemistry or shared pest pressure. See the full lettuce companion planting guide for the complete list.

Lettuce Planting Dates by City in California

Top cities in California — select for city-level frost dates and planting calendars.

Frequently Asked Questions

When should I plant lettuce in California?

In California (Zone 9b), start lettuce seeds indoors around December 18–25 and transplant outdoors around December 18–28 — 4 weeks before the state's average last frost of January 15.

What is the last frost date in California?

California's average last frost date is January 15 in the state's most common Zone 9b. Frost dates vary by city — higher elevations and northern counties run 1 to 3 weeks later than the state average. See the city list below for city-level frost dates.

Can I grow lettuce year-round in California?

lettuce is a cool-season crop in California, with spring and fall windows. Summer heat bolts the plants before they can produce a harvestable crop. Succession planting every 2–3 weeks stretches the harvest window.

What lettuce varieties grow best in California?

For California's Zone 9b, Bolt-resistant Jericho, Slobolt, and Summer Bibb extend the usable spring window.

When do I start lettuce seeds indoors in California?

Start lettuce seeds indoors in California around December 18–25, which is 4 weeks before the state's average last frost of January 15. Use grow lights and keep soil temperatures at 70–75°F for fastest germination.

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