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When to plant Arugula in Isleton, CA

Aim to plant Arugula in Isleton on or after January 22; the window stays open through February 12. Isleton's 293-day frost-free season gives you plenty of room for a spring and fall cycle. A second sowing from October 6 to October 20 extends the harvest into fall.

When to Plant Arugula in Isleton, CA

Sacramento County, California Zone 9b August

Your August planting checklist for Sacramento County, California

Your Sacramento County, California garden is entering a new phase. Here's what's on the schedule for August and why each task matters now.

Avg. last frost February 12
Avg. first frost December 1
Soil temp (4") 94°F
Watering Critical
Pest pressure High
Daylight 13.5 hrs

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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.

Isleton, California is in USDA Zone 9b. The average last spring frost is February 12 and the first fall frost is December 1, giving you a growing season of approximately 292 days.

At an elevation of 263 feet, Sacramento County receives approximately 33.2 inches of rainfall annually with predominantly loam soil. Summer highs average 90°F, providing good warmth for Arugula during the growing season.

Isleton, CA (Zone 9b) Year-round
292 days
Last Spring Frost February 12
292 growing days
First Fall Frost December 1

Isleton Soil Profile

Soil Type

Loam

Soil pH

6.4-7.1

Drainage

Well Drained

Arugula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (205 days to spare)
Start indoors: Dec 29 Transplant: Jan 26 🍅 Harvest: Mar 2 – May 4
Recommended (50%) ✓ Fits season (194 days to spare)
Start indoors: Jan 15 Transplant: Feb 12 🍅 Harvest: Mar 19 – May 21
Safe Start (90%) ✓ Fits season (160 days to spare)
Start indoors: Mar 9 Transplant: Apr 6 🍅 Harvest: May 11 – Jul 13

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 Isleton

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

Soil pH

Your soil pH (6.4–7.1) overlaps with Arugula's range (6.0–7.0), though not a perfect match.

Soil Texture

The loam soil in Sacramento County is excellent for Arugula — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.4%). 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

11
successive plantings in your 292-day season

Sow every 3.4 weeks. Last sowing by Oct 12 to harvest before frost.

For a dedicated fall crop, sow by Oct 06.

Arugula Water Budget

Plant needs
0.6″/week
Rainfall provides
0.5″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 388 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — 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 6.1" 0" ❄️ Dormant
Feb 2.6" 7.5" 0" ✅ Rainfall sufficient
Mar 2.6" 5.7" 0" ✅ Rainfall sufficient
Apr 2.6" 2.5" 0.1" 💧 Light watering
May 2.6" 0.8" 1.8" 🚿 Regular watering
Jun 2.6" 0.2" 2.4" 🚿 Regular watering
Jul 2.6" 0" 2.6" 🚿 Regular watering
Aug 2.6" 0" 2.6" 🚿 Regular watering
Sep 2.6" 0.3" 2.3" 🚿 Regular watering
Oct 2.6" 1.4" 1.2" 💧 Light watering
Nov 2.6" 2.7" 0" ✅ Rainfall sufficient
Dec 2.6" 5.9" 0" ✅ Rainfall sufficient

Water needs are for active growing months only (Feb–Dec in Sacramento County). Supplement amounts are based on average rainfall — 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" — 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.

Arugula needs ~700 GDD — county provides 5,127 GDD Excellent fit

Arugula Planting Timeline — Isleton, CA

Arugula Planting Calendar

Activity When Date Range
Start Indoors January 15 Jan 15 – Jan 29
Transplant Outdoors February 12 Feb 12 – Feb 26
Direct Sow January 22 Jan 22 – Feb 12
Harvest March 19 Mar 19 – May 21
Fall Sowing October 6 Oct 6 – Oct 20

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.6"/week · Only during dry spells

📅 Days to Maturity

30–50 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 9b

📆 Growing Season

292 days in Sacramento County

Growing Tips for Arugula in Isleton

Direct sow Arugula outdoors after February 12 in Sacramento County when soil has warmed and frost danger has passed.

Your generous 293.0-day season in Sacramento 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 →

When should I plant Arugula in Isleton, CA?

In Isleton, CA, plant Arugula after the last frost (around February 12) and before the first frost (around December 1). Best results when soil holds above 50°F.

What growing zone is Isleton, CA for Arugula?

Isleton sits in USDA Zone 9b. Arugula grows reliably in zones 3a through 11b, so it's a good fit here.

Can Arugula grow in Isleton's climate?

Yes — Arugula grows well in Isleton's temperate climate. Isleton averages a 293-day frost-free season, with last frost around February 12 and first frost around December 1.

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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 Sacramento County, CA. Local conditions may vary. Last updated: August 2026.