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When to plant Arugula in Cook County County,

Plant Arugula in Cook County County, when soil hits 50°F — usually April 9. Continue planting through April 30 for the spring crop. A second sowing from August 8 to August 22 extends the harvest into fall.

When to Plant Arugula in Cook County, IL

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.

Cook County, Illinois is in USDA Zone 6a. The average last spring frost is April 23 and the first fall frost is October 17, giving you a growing season of approximately 177 days.

At an elevation of 728 feet, Cook County receives approximately 35.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Arugula during the growing season.

Cook County, IL (Zone 6a) Moderate season
177 days
Last Spring Frost April 23
177 growing days
First Fall Frost October 17

Cook County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7

Drainage

Well Drained

Monthly Watering Guide for Arugula

Arugula needs approximately 1 inches of water per week (4.3" 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 2.7" 0" ❄️ Dormant
Apr 4.3" 3.6" 0.7" 💧 Light watering
May 4.3" 4.1" 0.2" 💧 Light watering
Jun 4.3" 4.7" 0" ✅ Rainfall sufficient
Jul 4.3" 3.7" 0.6" 💧 Light watering
Aug 4.3" 3.2" 1.1" 💧 Light watering
Sep 4.3" 2.9" 1.4" 💧 Light watering
Oct 4.3" 3" 1.3" 💧 Light watering
Nov 2.3" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Cook County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Arugula Planting Timeline — Cook County, IL

Arugula Planting Calendar

Activity When Date Range
Start Indoors March 19 Mar 19 – Apr 2
Transplant Outdoors April 23 Apr 23 – May 7
Direct Sow April 9 Apr 9 – Apr 30
Harvest May 28 May 28 – Jul 30
Fall Sowing August 8 Aug 8 – Aug 22

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

30–50 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 6a

📆 Growing Season

177 days in Cook County

Growing Tips for Cook County

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 Cook County, IL?

Cook County is in Zone 6a with an average last frost of April 23. Plan your Arugula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Cook County, IL?

Cook County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 23 and first fall frost is October 17.

When should I plant Arugula in Cook County County, ?

In Cook County County, , plant Arugula after the last frost (around April 23) and before the first frost (around October 17). Best results when soil holds above 50°F.

What growing zone is Cook County County, for Arugula?

Cook County County sits in USDA Zone 6a. Arugula grows reliably in zones 3a through 11b, so it's a good fit here.

Can Arugula grow in Cook County County's climate?

Yes — Arugula grows well in Cook County County's temperate climate. Cook County County averages a 177-day frost-free season, with last frost around April 23 and first frost around October 17.

🌱

Your Cook County Garden Planner — Free

A 22-page printable planner built for Cook County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Cook County, IL. Local conditions may vary. Last updated: June 2026.

Sources & credits

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