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When to Plant Celtuce in Monterey County, CA

Celtuce (stem lettuce) is a Chinese vegetable grown for its thick, crunchy stem rather than its leaves. The peeled stem has a mild, cucumber-like flavor.

Monterey County, California is in USDA Zone 9b. The average last spring frost is March 13 and the first fall frost is November 17, giving you a growing season of approximately 249 days.

At an elevation of 260 feet, Monterey County receives approximately 12.5 inches of rainfall annually with predominantly loam soil. Summer highs average 93ยฐF, providing good warmth for Celtuce during the growing season. With low rainfall, drip irrigation is essential for growing Celtuce successfully. Mulch heavily to conserve soil moisture.

Monterey County, CA (Zone 9b) Long season
249 days
Last Spring Frost March 13
249 growing days
First Fall Frost November 17

Monterey County Soil Profile

Soil Type

Loam

Soil pH

6.7-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (143 days to spare)
Start indoors: Jan 30 Transplant: Feb 27 🍅 Harvest: May 1 – Jun 12
Recommended (50%) ✓ Fits season (144 days to spare)
Start indoors: Feb 13 Transplant: Mar 13 🍅 Harvest: May 15 – Jun 26
Safe Start (90%) ✓ Fits season (109 days to spare)
Start indoors: Apr 19 Transplant: May 17 🍅 Harvest: Jul 19 – Aug 30

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 Monterey County

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

Soil pH

Your soil pH (6.7โ€“7.2) overlaps with Celtuce's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

The loam soil in Monterey County is excellent for Celtuce โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.7%). Annual compost additions will help Celtuce.

How to Plant Celtuce

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 Celtuce

4
successive plantings in your 249-day season

Sow every 6.9 weeks. Last sowing by Aug 19 to harvest before frost.

For a dedicated fall crop, sow by Sep 22.

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 1,301 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Celtuce

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

Month Celtuce Needs Rainfall You Supplement Action
Jan โ€” 2.7" 0" โ„๏ธ Dormant
Feb โ€” 2.6" 0" โ„๏ธ Dormant
Mar 3" 2.1" 0.9" ๐Ÿ’ง Light watering
Apr 3" 1" 2" ๐Ÿšฟ Regular watering
May 3" 0.3" 2.7" ๐Ÿšฟ Regular watering
Jun 3" 0.1" 2.9" ๐Ÿšฟ Regular watering
Jul 3" 0" 3" ๐Ÿšฟ Regular watering
Aug 3" 0" 3" ๐Ÿšฟ Regular watering
Sep 3" 0.1" 2.9" ๐Ÿšฟ Regular watering
Oct 3" 0.5" 2.5" ๐Ÿšฟ Regular watering
Nov 3" 1.2" 1.8" ๐Ÿšฟ Regular watering
Dec โ€” 1.9" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Monterey County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Celtuce 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" โ€” every day above 50ยฐF 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.

Celtuce needs ~1,481 GDD — county provides 4,917 GDD Excellent fit

Celtuce Planting Timeline โ€” Monterey County, CA

Celtuce Planting Calendar

Activity When Date Range
Start Indoors February 13 Feb 13 โ€“ Feb 27
Transplant Outdoors March 13 Mar 13 โ€“ Mar 27
Direct Sow February 20 Feb 20 โ€“ Mar 13
Harvest May 15 May 15 โ€“ Jun 26
Fall Sowing September 22 Sep 22 โ€“ Oct 6

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.7"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

60โ€“90 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 9b

๐Ÿ“† Growing Season

249 days in Monterey County

Growing Tips for Celtuce in Monterey County

Direct sow Celtuce outdoors after March 13 in Monterey County when soil has warmed and frost danger has passed.

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

General growing tips

Direct sow in spring or start indoors. Space 12 inches apart. Harvest when stems are about 1 inch in diameter. Peel the tough outer skin to reveal the tender center.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Celtuce in Monterey County, CA?

Monterey County is in Zone 9b with an average last frost of March 13. Plan your Celtuce planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Monterey County, CA?

Monterey County, California is in USDA Hardiness Zone 9b. The average last spring frost is March 13 and first fall frost is November 17.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Monterey County gardeners in Zone 9b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Monterey County, CA. Local conditions may vary. Last updated: April 2026.