Blog

When to Plant Arugula in Lake County, OR

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.

Lake County, Oregon is in USDA Zone 5b. The average last spring frost is June 16 and the first fall frost is September 7, giving you a growing season of approximately 83 days.

At an elevation of 1,236 feet, Lake County receives approximately 12.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88ยฐF, 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.

Lake County, OR (Zone 5b) Very short season
83 days
Last Spring Frost June 16
83 growing days
First Fall Frost September 7

Lake County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Apr 28 Transplant: Jun 2 🍅 Harvest: Jul 7 – Sep 8
Recommended (50%) ✗ May not fit
Start indoors: May 12 Transplant: Jun 16 🍅 Harvest: Jul 21 – Sep 22
Safe Start (90%) ✗ May not fit
Start indoors: May 22 Transplant: Jun 26 🍅 Harvest: Jul 31 – Oct 2

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 Lake County

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

Soil pH

Your soil pH (5.7โ€“6.4) overlaps with Arugula's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.4%) โ€” Arugula will thrive.

How to Plant Arugula

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Arugula

3
successive plantings in your 83-day season

Sow every 3.4 weeks. Last sowing by Jul 19 to harvest before frost.

For a dedicated fall crop, sow by Jun 29.

Plant Water Budget

Plant needs
0.6″/week
Rainfall provides
0.7″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

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€” 2" 0" โ„๏ธ Dormant
Feb โ€” 1.3" 0" โ„๏ธ Dormant
Mar โ€” 1.3" 0" โ„๏ธ Dormant
Apr โ€” 0.8" 0" โ„๏ธ Dormant
May โ€” 0.7" 0" โ„๏ธ Dormant
Jun 2.6" 0.5" 2.1" ๐Ÿšฟ Regular watering
Jul 2.6" 0.2" 2.4" ๐Ÿšฟ Regular watering
Aug 2.6" 0.2" 2.4" ๐Ÿšฟ Regular watering
Sep 2.6" 0.5" 2.1" ๐Ÿšฟ Regular watering
Oct โ€” 1.2" 0" โ„๏ธ Dormant
Nov โ€” 1.9" 0" โ„๏ธ Dormant
Dec โ€” 2.1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Junโ€“Sep in Lake 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 ~640 GDD — county provides 1,328 GDD Excellent fit

Arugula Planting Timeline โ€” Lake County, OR

Arugula Planting Calendar

Activity When Date Range
Start Indoors May 12 May 12 โ€“ May 26
Transplant Outdoors June 16 Jun 16 โ€“ Jun 30
Direct Sow June 2 Jun 2 โ€“ Jun 23
Harvest July 21 Jul 21 โ€“ Sep 22
Fall Sowing June 29 Jun 29 โ€“ Jul 13

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

0.6"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

30โ€“50 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

83 days in Lake County

Growing Tips for Arugula in Lake County

Direct sow Arugula outdoors after June 16 in Lake County when soil has warmed and frost danger has passed.

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 Lake County, OR?

Lake County is in Zone 5b with an average last frost of June 16. Plan your Arugula planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Lake County, OR?

Lake County, Oregon is in USDA Hardiness Zone 5b. The average last spring frost is June 16 and first fall frost is September 7.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Lake County gardeners in Zone 5b 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 Lake County, OR. Local conditions may vary. Last updated: April 2026.