When to plant Leeks in Roseau County, MN
For Leeks in Roseau County, the safe spring window opens around May 14 and closes around June 4. Last expected frost is May 21, first fall frost September 22, giving a 124-day growing season. A second sowing from June 30 to July 14 extends the harvest into fall.
When to Plant Leeks in Roseau County, MN
Your July game plan for Roseau County, Minnesota
Your Roseau County, Minnesota garden is entering a new phase. Here's what's on the schedule for July and why each task matters now.
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Get leeks seeds going inside
Starting these indoors now means sturdy transplants ready the moment your soil warms up.
Before August arrives, get these ready
- First harvests: 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.
Roseau County, Minnesota is in USDA Zone 3b. The average last spring frost is May 21 and the first fall frost is September 22, giving you a growing season of approximately 124 days.
At an elevation of 655 feet, Roseau County receives approximately 32 inches of rainfall annually with predominantly silt loam soil. Summer highs average 79°F, so choose short-season varieties of Leeks to ensure they mature before fall.
Roseau County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-7.2
Drainage
Well Drained
Leeks 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 Roseau County
How your county's soil matches Leeks's growing requirements.
Soil pH
Your soil pH (5.9–7.2) overlaps with Leeks's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Roseau County is excellent for Leeks — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.1%) — Leeks will thrive.
How to Plant Leeks
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Leeks 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 | — | 1.2" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 1.8" | 0" | ❄️ Dormant |
| Apr | — | 2.9" | 0" | ❄️ Dormant |
| May | 3.5" | 3.9" | 0" | ✅ Rainfall sufficient |
| Jun | 3.5" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jul | 3.5" | 3.8" | 0" | ✅ Rainfall sufficient |
| Aug | 3.5" | 3.7" | 0" | ✅ Rainfall sufficient |
| Sep | 3.5" | 2.4" | 1.1" | 💧 Light watering |
| Oct | — | 2.7" | 0" | ❄️ Dormant |
| Nov | — | 1.9" | 0" | ❄️ Dormant |
| Dec | — | 1.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Roseau 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 — Roseau County, MN
Leeks Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 9 | Apr 9 – Apr 23 |
| Transplant Outdoors | May 21 | May 21 – Jun 4 |
| Direct Sow | May 14 | May 14 – Jun 4 |
| Harvest | August 20 | Aug 20 – Sep 24 |
| Fall Sowing | June 30 | Jun 30 – Jul 14 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow Fall Sowing |
| July | Fall Sowing |
| August | Harvest |
| September | Harvest |
| October | — |
| 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 3b
📆 Growing Season
124 days in Roseau County
Growing Tips for Leeks in Roseau County
Direct sow Leeks outdoors after May 21 in Roseau County when soil has warmed and frost danger has passed.
Your 124.0-day growing season in Roseau 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
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Leeks in Other Locations
Frequently Asked Questions
When should I plant Leeks in Roseau County, MN?
Roseau County is in Zone 3b with an average last frost of May 21. Plan your Leeks planting based on this frost date — see the calendar above for exact timing.
What planting zone is Roseau County, MN?
Roseau County, Minnesota is in USDA Hardiness Zone 3b. The average last spring frost is May 21 and first fall frost is September 22.
When should I plant Leeks in Roseau County, MN?
In Roseau County, MN, plant Leeks after the last frost (around May 21) and before the first frost (around September 22). Best results when soil holds above 50°F.
What growing zone is Roseau County, MN for Leeks?
Roseau 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 Roseau County's climate?
Yes — Leeks grows well in Roseau County's temperate climate. Roseau County averages a 124-day frost-free season, with last frost around May 21 and first frost around September 22.
Your Roseau County Garden Planner — Free
A 22-page printable planner built for Roseau 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.