When to Plant Leeks in Lake County, MI
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.
Lake County, Michigan is in USDA Zone 5a. The average last spring frost is May 14 and the first fall frost is October 6, giving you a growing season of approximately 145 days.
At an elevation of 733 feet, Lake County receives approximately 33.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Leeks during the growing season.
Lake County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-7.1
Drainage
Well Drained
Plant Planting Risk Windows
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 Lake County
How your county's soil matches Leeks's growing requirements.
Soil pH
Your soil pH (6.2–7.1) overlaps with Leeks's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Lake County is excellent for Leeks — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.9%) — Leeks will thrive.
How to Plant Leeks
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Plant Water Budget
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 | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.1" | 0" | ❄️ Dormant |
| Apr | — | 3.7" | 0" | ❄️ Dormant |
| May | 3.5" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jun | 3.5" | 3.7" | 0" | ✅ Rainfall sufficient |
| Jul | 3.5" | 3.9" | 0" | ✅ Rainfall sufficient |
| Aug | 3.5" | 3.2" | 0.3" | 💧 Light watering |
| Sep | 3.5" | 3.3" | 0.2" | 💧 Light watering |
| Oct | 3.5" | 2.8" | 0.7" | 💧 Light watering |
| Nov | — | 2" | 0" | ❄️ Dormant |
| Dec | — | 1.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Lake 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 Planting Timeline — Lake County, MI
Leeks Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 9 | Apr 9 – Apr 23 |
| Transplant Outdoors | May 14 | May 14 – May 28 |
| Direct Sow | April 30 | Apr 30 – May 21 |
| Harvest | August 13 | Aug 13 – Oct 29 |
| Fall Sowing | July 28 | Jul 28 – Aug 11 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Fall Sowing |
| 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 5a
📆 Growing Season
145 days in Lake County
Growing Tips for Leeks in Lake County
Direct sow Leeks outdoors after May 14 in Lake County when soil has warmed and frost danger has passed.
Your 145.0-day growing season in Lake County is tight for Leeks (90.0-150.0 days to maturity). Start indoors and choose early-maturing varieties.
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
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Check more plant combinations with our Companion Planting Checker →
Leeks in Other Locations
Frequently Asked Questions
When should I plant Leeks in Lake County, MI?
Lake County is in Zone 5a with an average last frost of May 14. Plan your Leeks planting based on this frost date — see the calendar above for exact timing.
What planting zone is Lake County, MI?
Lake County, Michigan is in USDA Hardiness Zone 5a. The average last spring frost is May 14 and first fall frost is October 6.
Plan Your Garden with Confidence
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