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When to plant Leeks in Carlton County, MN

Carlton County's climate puts the Leeks spring window between May 5 and May 26. be cautious and check the 10-day forecast before planting tender crops. A second sowing from July 10 to July 24 extends the harvest into fall.

When to Plant Leeks in Carlton 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.

Carlton County, Minnesota is in USDA Zone 4a. The average last spring frost is May 12 and the first fall frost is October 2, giving you a growing season of approximately 143 days.

At an elevation of 516 feet, Carlton County receives approximately 32.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Leeks to ensure they mature before fall.

Carlton County, MN (Zone 4a) Short season
143 days
Last Spring Frost May 12
143 growing days
First Fall Frost October 2

Carlton County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-7.1

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 1.5" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 3.1" 0" ❄️ Dormant
May 4.3" 3.4" 0.9" 💧 Light watering
Jun 4.3" 4.1" 0.2" 💧 Light watering
Jul 4.3" 3.5" 0.8" 💧 Light watering
Aug 4.3" 3.4" 0.9" 💧 Light watering
Sep 4.3" 2.7" 1.6" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 2.5" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

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

Leeks Planting Timeline — Carlton County, MN

Leeks Planting Calendar

Activity When Date Range
Start Indoors March 31 Mar 31 – Apr 14
Transplant Outdoors May 12 May 12 – May 26
Direct Sow May 5 May 5 – May 26
Harvest August 11 Aug 11 – Oct 6
Fall Sowing July 10 Jul 10 – Jul 24

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 Harvest
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 4a

📆 Growing Season

143 days in Carlton County

Growing Tips for Carlton 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 Carlton County, MN?

Carlton County is in Zone 4a with an average last frost of May 12. Plan your Leeks planting based on this frost date — see the calendar above for exact timing.

What planting zone is Carlton County, MN?

Carlton County, Minnesota is in USDA Hardiness Zone 4a. The average last spring frost is May 12 and first fall frost is October 2.

When should I plant Leeks in Carlton County, MN?

In Carlton County, MN, plant Leeks after the last frost (around May 12) and before the first frost (around October 2). Best results when soil holds above 50°F.

What growing zone is Carlton County, MN for Leeks?

Carlton County sits in USDA Zone 4a. Leeks grows reliably in zones 3a through 10b, so it's a good fit here.

Can Leeks grow in Carlton County's climate?

Yes — Leeks grows well in Carlton County's temperate climate. Carlton County averages a 143-day frost-free season, with last frost around May 12 and first frost around October 2.

🌱

Your Carlton County Garden Planner — Free

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

Sources & credits

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