Blog

When to Plant Arugula in Lake County, MI

Lake County, Michigan Zone 5b May

May in the garden — Lake County, Michigan

If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.

Avg. last frost May 14
Avg. first frost October 6
Soil temp (4") 60°F
Watering Low
Pest pressure Low
Daylight 14.6 hrs
  1. Harden off and plant arugula

    Pinch off the lowest leaves on each seedling before you plant — it reduces water loss while the roots catch up.

Before June arrives, get these ready
  • Starting indoors: arugula
  • First harvests: arugula

Instant PDF download. No spam, unsubscribe any time.

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, Michigan is in USDA Zone 5b. The average last spring frost is May 14 and the first fall frost is October 6, giving you a growing season of approximately 145 days.

At an elevation of 733 feet, Lake County receives approximately 33.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Arugula during the growing season.

Lake County, MI (Zone 5b) Short season
145 days
Last Spring Frost May 14
145 growing days
First Fall Frost October 6
Share this guide:

Lake County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (48 days to spare)
Start indoors: Apr 3 Transplant: May 8 🍅 Harvest: Jun 12 – Aug 14
Recommended (50%) ✓ Fits season (47 days to spare)
Start indoors: Apr 9 Transplant: May 14 🍅 Harvest: Jun 18 – Aug 20
Safe Start (90%) ✓ Fits season (52 days to spare)
Start indoors: Apr 21 Transplant: May 26 🍅 Harvest: Jun 30 – Sep 1

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 (6.2–7.1) overlaps with Arugula's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.9%) — 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

5
successive plantings in your 145-day season

Sow every 3.4 weeks. Last sowing by Aug 17 to harvest before frost.

For a dedicated fall crop, sow by Jul 28.

Plant Water Budget

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

Water stress score is 6/10 — 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 1.5" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.1" 0" ❄️ Dormant
Apr 3.7" 0" ❄️ Dormant
May 2.6" 4.3" 0" ✅ Rainfall sufficient
Jun 2.6" 3.7" 0" ✅ Rainfall sufficient
Jul 2.6" 3.9" 0" ✅ Rainfall sufficient
Aug 2.6" 3.2" 0" ✅ Rainfall sufficient
Sep 2.6" 3.3" 0" ✅ Rainfall sufficient
Oct 2.6" 2.8" 0" ✅ Rainfall sufficient
Nov 2" 0" ❄️ Dormant
Dec 1.6" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Lake 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 ~580 GDD — county provides 2,102 GDD Excellent fit

Arugula Planting Timeline — Lake County, MI

Arugula Planting Calendar

Activity When Date Range
Start Indoors April 9 Apr 9 – Apr 23
Transplant Outdoors May 14 May 14 – May 28
Direct Sow April 30 Apr 30 – May 21
Harvest June 18 Jun 18 – Aug 20
Fall Sowing July 28 Jul 28 – Aug 11

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.6"/week · Natural rainfall sufficient

📅 Days to Maturity

30–50 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 5b

📆 Growing Season

145 days in Lake County

Growing Tips for Arugula in Lake County

Direct sow Arugula outdoors after May 14 in Lake County when soil has warmed and frost danger has passed.

Your generous 145.0-day season in Lake 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 Lake County, MI?

Lake County is in Zone 5b with an average last frost of May 14. Plan your Arugula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lake County, MI?

Lake County, Michigan is in USDA Hardiness Zone 5b. The average last spring frost is May 14 and first fall frost is October 6.

🌱

Your Lake County Garden Planner — Free

A 24-page printable planner built for Lake County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.