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When to Plant Arugula in Santa Barbara County, CA

Arugula is a fast-growing cool-season green with a peppery, nutty flavor. It is excellent in salads and can be harvested as baby greens or mature leaves.

Santa Barbara County, California is in USDA Zone 10a. The average last spring frost is February 28 and the first fall frost is November 24, giving you a growing season of approximately 269 days.

At an elevation of 2,364 feet, Santa Barbara County receives approximately 19.9 inches of rainfall annually with predominantly loam soil. Summer highs average 89ยฐF, providing good warmth for Arugula during the growing season. With low rainfall, drip irrigation is essential for growing Arugula successfully. Mulch heavily to conserve soil moisture.

Santa Barbara County, CA (Zone 10a) Long season
269 days
Last Spring Frost February 28
269 growing days
First Fall Frost November 24

Santa Barbara County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (175 days to spare)
Start indoors: Jan 15 Transplant: Feb 12 🍅 Harvest: Mar 19 – May 21
Recommended (50%) ✓ Fits season (171 days to spare)
Start indoors: Jan 31 Transplant: Feb 28 🍅 Harvest: Apr 4 – Jun 6
Safe Start (90%) ✓ Fits season (159 days to spare)
Start indoors: Mar 10 Transplant: Apr 7 🍅 Harvest: May 12 – Jul 14

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 Santa Barbara County

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

Soil pH

Your soil pH (6.5โ€“7.2) overlaps with Arugula's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.8%). Annual compost additions will help Arugula.

How to Plant Arugula

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 Arugula

10
successive plantings in your 269-day season

Sow every 3.4 weeks. Last sowing by Oct 05 to harvest before frost.

For a dedicated fall crop, sow by Sep 29.

Plant Water Budget

Plant needs
0.6″/week
Rainfall provides
0.3″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 838 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Arugula

Arugula needs approximately 0.6 inches of water per week (2.6" per month). Here's how your county's rainfall compares month by month.

Month Arugula Needs Rainfall You Supplement Action
Jan โ€” 4" 0" โ„๏ธ Dormant
Feb 2.6" 4.6" 0" โœ… Rainfall sufficient
Mar 2.6" 2.9" 0" โœ… Rainfall sufficient
Apr 2.6" 1.8" 0.8" ๐Ÿ’ง Light watering
May 2.6" 0.5" 2.1" ๐Ÿšฟ Regular watering
Jun 2.6" 0.1" 2.5" ๐Ÿšฟ Regular watering
Jul 2.6" 0" 2.6" ๐Ÿšฟ Regular watering
Aug 2.6" 0" 2.6" ๐Ÿšฟ Regular watering
Sep 2.6" 0.2" 2.4" ๐Ÿšฟ Regular watering
Oct 2.6" 0.8" 1.8" ๐Ÿšฟ Regular watering
Nov 2.6" 2.1" 0.5" ๐Ÿ’ง Light watering
Dec โ€” 2.9" 0" โ„๏ธ Dormant

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

Arugula 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.

Arugula needs ~670 GDD — county provides 4,522 GDD Excellent fit

Arugula Planting Timeline โ€” Santa Barbara County, CA

Arugula Planting Calendar

Activity When Date Range
Start Indoors January 31 Jan 31 โ€“ Feb 14
Transplant Outdoors February 28 Feb 28 โ€“ Mar 14
Direct Sow February 7 Feb 7 โ€“ Feb 28
Harvest April 4 Apr 4 โ€“ Jun 6
Fall Sowing September 29 Sep 29 โ€“ Oct 13

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

0.6"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

30โ€“50 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 10a

๐Ÿ“† Growing Season

269 days in Santa Barbara County

Growing Tips for Arugula in Santa Barbara County

Direct sow Arugula outdoors after February 28 in Santa Barbara County when soil has warmed and frost danger has passed.

Your generous 270.0-day season in Santa Barbara County allows multiple plantings of Arugula. Sow every 15.0 days for continuous harvest.

Common pests for Arugula in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Sow seeds directly every 2-3 weeks for continuous harvest. Provide afternoon shade in warm weather to prevent bolting. Harvest outer leaves first to extend production.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Arugula in Santa Barbara County, CA?

Santa Barbara County is in Zone 10a with an average last frost of February 28. Plan your Arugula planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Santa Barbara County, CA?

Santa Barbara County, California is in USDA Hardiness Zone 10a. The average last spring frost is February 28 and first fall frost is November 24.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Santa Barbara County gardeners in Zone 10a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

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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 Santa Barbara County, CA. Local conditions may vary. Last updated: April 2026.