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When to plant Leeks in Applegate,

Applegate's spring Leeks window runs April 20 through May 11. time plantings around the expected last-frost window for best survival. A second sowing from August 8 to August 22 extends the harvest into fall.

When to Plant Leeks in Applegate, MI

Leeks
Applegate, MI Zone 6a June

What to do in June

Your Applegate, MI garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.

Avg. last frost May 4
Avg. first frost October 17
Soil temp (4") 70°F
Watering Low
Pest pressure High
Daylight 15.2 hrs
  1. Fire up the seed-starting tray: leeks

    These need a head start before your last frost (May 4). Sow into cells now so you're ready to transplant in a few weeks.

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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.

Applegate, Michigan is in USDA Zone 6a. The average last spring frost is May 4 and the first fall frost is October 17, giving you a growing season of approximately 166 days.

At an elevation of 985 feet, Sanilac County receives approximately 37 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Leeks during the growing season.

Applegate, MI (Zone 6a) Moderate season
166 days
Last Spring Frost May 4
166 growing days
First Fall Frost October 17

Applegate Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-7

Drainage

Well Drained

Leeks Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Mar 25 Transplant: Apr 29 🍅 Harvest: Jul 29 – Oct 14
Recommended (50%) ✗ May not fit
Start indoors: Mar 30 Transplant: May 4 🍅 Harvest: Aug 3 – Oct 19
Safe Start (90%) ✗ May not fit
Start indoors: Apr 16 Transplant: May 21 🍅 Harvest: Aug 20 – Nov 5

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 Applegate

How your county's soil matches Leeks's growing requirements.

Soil pH

Your soil pH (5.7–7.0) overlaps with Leeks's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (4.0%). Annual compost additions will help Leeks.

How to Plant Leeks

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Leeks Water Budget

Plant needs
0.8″/week
Rainfall provides
0.9″/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 Leeks

Leeks needs approximately 0.8 inches of water per week (3.5" 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 1.7" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 3.9" 0" ❄️ Dormant
May 3.5" 3.9" 0" ✅ Rainfall sufficient
Jun 3.5" 4.9" 0" ✅ Rainfall sufficient
Jul 3.5" 4.5" 0" ✅ Rainfall sufficient
Aug 3.5" 3.4" 0.1" 💧 Light watering
Sep 3.5" 3.8" 0" ✅ Rainfall sufficient
Oct 3.5" 2.8" 0.7" 💧 Light watering
Nov 2.3" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

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

Leeks 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.

Leeks needs ~1,740 GDD — county provides 2,407 GDD Excellent fit

Leeks Planting Timeline — Applegate, MI

Leeks Planting Calendar

Activity When Date Range
Start Indoors March 30 Mar 30 – Apr 13
Transplant Outdoors May 4 May 4 – May 18
Direct Sow April 20 Apr 20 – May 11
Harvest August 3 Aug 3 – Oct 19
Fall Sowing August 8 Aug 8 – Aug 22

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.8"/week · Natural rainfall sufficient

📅 Days to Maturity

90–150 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6a

📆 Growing Season

166 days in Sanilac County

Growing Tips for Leeks in Applegate

Direct sow Leeks outdoors after May 04 in Sanilac County when soil has warmed and frost danger has passed.

Common pests for Leeks in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.

General growing tips

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 →

When should I plant Leeks in Applegate, ?

In Applegate, , plant Leeks after the last frost (around May 4) and before the first frost (around October 17). Best results when soil holds above 50°F.

What growing zone is Applegate, for Leeks?

Applegate sits in USDA Zone 6a. Leeks grows reliably in zones 3a through 10b, so it's a good fit here.

Can Leeks grow in Applegate's climate?

Yes — Leeks grows well in Applegate's temperate climate. Applegate averages a 166-day frost-free season, with last frost around May 4 and first frost around October 17.

🌱

Your Sanilac County Garden Planner — Free

A 22-page printable planner built for Sanilac 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 Sanilac County, MI. Local conditions may vary. Last updated: June 2026.