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When to plant Leeks in Pennington County, MN

Spring Leeks in Pennington County goes in May 3–May 24, once nighttime temps stop dipping near freezing. A second sowing from July 8 to July 22 extends the harvest into fall.

When to Plant Leeks in Pennington County, MN

Leeks

Leeks are a mild, sweet allium that produces long white shanks. They are more refined than onions and are a key ingredient in soups, stews, and gratins.

Pennington County, Minnesota is in USDA Zone 3b. The average last spring frost is May 10 and the first fall frost is September 30, giving you a growing season of approximately 143 days.

At an elevation of 854 feet, Pennington County receives approximately 35.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°F, so choose short-season varieties of Leeks to ensure they mature before fall.

Pennington County, MN (Zone 3b) Short season
143 days
Last Spring Frost May 10
143 growing days
First Fall Frost September 30

Pennington County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.1

Drainage

Well Drained

Monthly Watering Guide for Leeks

Leeks needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Leeks Needs Rainfall You Supplement Action
Jan 1.3" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 2.6" 0" ❄️ Dormant
Apr 3.3" 0" ❄️ Dormant
May 4.3" 4.3" 0" ✅ Rainfall sufficient
Jun 4.3" 4.4" 0" ✅ Rainfall sufficient
Jul 4.3" 3.9" 0.4" 💧 Light watering
Aug 4.3" 3" 1.3" 💧 Light watering
Sep 4.3" 3.3" 1" 💧 Light watering
Oct 2.9" 0" ❄️ Dormant
Nov 2.6" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

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

Leeks Planting Timeline — Pennington County, MN

Leeks Planting Calendar

Activity When Date Range
Start Indoors March 29 Mar 29 – Apr 12
Transplant Outdoors May 10 May 10 – May 24
Direct Sow May 3 May 3 – May 24
Harvest August 9 Aug 9 – Sep 13
Fall Sowing July 8 Jul 8 – Jul 22

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

90–150 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 3b

📆 Growing Season

143 days in Pennington County

Growing Tips for Pennington County

Start seeds indoors 10-12 weeks before last frost. Transplant into trenches and hill soil around stems as they grow to increase the white portion. Harvest as needed.

Companion Planting

Good Companions

Avoid Planting Near

  • Peas
  • Green Beans

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Leeks in Pennington County, MN?

Pennington County is in Zone 3b with an average last frost of May 10. Plan your Leeks planting based on this frost date — see the calendar above for exact timing.

What planting zone is Pennington County, MN?

Pennington County, Minnesota is in USDA Hardiness Zone 3b. The average last spring frost is May 10 and first fall frost is September 30.

When should I plant Leeks in Pennington County, MN?

In Pennington County, MN, plant Leeks after the last frost (around May 10) and before the first frost (around September 30). Best results when soil holds above 50°F.

What growing zone is Pennington County, MN for Leeks?

Pennington County sits in USDA Zone 3b. Leeks grows reliably in zones 3a through 10b, so it's a good fit here.

Can Leeks grow in Pennington County's climate?

Yes — Leeks grows well in Pennington County's temperate climate. Pennington County averages a 143-day frost-free season, with last frost around May 10 and first frost around September 30.

🌱

Your Pennington County Garden Planner — Free

A 22-page printable planner built for Pennington County (Zone 3b). 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 Pennington County, MN. Local conditions may vary. Last updated: July 2026.

Sources & credits

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