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When to plant Arugula in Douglas County, MN

In Zone 4b (Douglas County), direct-sow Arugula between April 26 and May 17 for spring, after the May 3 last-frost mark. A second sowing from July 12 to July 26 extends the harvest into fall.

When to Plant Arugula in Douglas County, MN

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.

Douglas County, Minnesota is in USDA Zone 4b. The average last spring frost is May 3 and the first fall frost is October 4, giving you a growing season of approximately 154 days.

At an elevation of 1,010 feet, Douglas County receives approximately 37.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°F, so choose short-season varieties of Arugula to ensure they mature before fall.

Douglas County, MN (Zone 4b) Moderate season
154 days
Last Spring Frost May 3
154 growing days
First Fall Frost October 4

Douglas County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-6.9

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 1.4" 0" ❄️ Dormant
Feb 1.7" 0" ❄️ Dormant
Mar 2.3" 0" ❄️ Dormant
Apr 3.4" 0" ❄️ Dormant
May 4.3" 4.5" 0" ✅ Rainfall sufficient
Jun 4.3" 5.2" 0" ✅ Rainfall sufficient
Jul 4.3" 4" 0.3" 💧 Light watering
Aug 4.3" 4" 0.3" 💧 Light watering
Sep 4.3" 2.9" 1.4" 💧 Light watering
Oct 4.3" 2.9" 1.4" 💧 Light watering
Nov 2.8" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

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

Arugula Planting Timeline — Douglas County, MN

Arugula Planting Calendar

Activity When Date Range
Start Indoors March 22 Mar 22 – Apr 5
Transplant Outdoors May 3 May 3 – May 17
Direct Sow April 26 Apr 26 – May 17
Harvest June 7 Jun 7 – Aug 9
Fall Sowing July 12 Jul 12 – Jul 26

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors Direct Sow
May Transplant Outdoors Direct Sow
June Harvest
July Fall Sowing Harvest
August Harvest
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 4b

📆 Growing Season

154 days in Douglas County

Growing Tips for Douglas 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 Douglas County, MN?

Douglas County is in Zone 4b with an average last frost of May 3. Plan your Arugula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Douglas County, MN?

Douglas County, Minnesota is in USDA Hardiness Zone 4b. The average last spring frost is May 3 and first fall frost is October 4.

When should I plant Arugula in Douglas County, MN?

In Douglas County, MN, plant Arugula after the last frost (around May 3) and before the first frost (around October 4). Best results when soil holds above 50°F.

What growing zone is Douglas County, MN for Arugula?

Douglas County sits in USDA Zone 4b. Arugula grows reliably in zones 3a through 11b, so it's a good fit here.

Can Arugula grow in Douglas County's climate?

Yes — Arugula grows well in Douglas County's temperate climate. Douglas County averages a 154-day frost-free season, with last frost around May 3 and first frost around October 4.

🌱

Your Douglas County Garden Planner — Free

A 22-page printable planner built for Douglas County (Zone 4b). 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 Douglas County, MN. Local conditions may vary. Last updated: June 2026.

Sources & credits

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