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When to plant Leeks in Gunnison County, CO

Gunnison County's spring Leeks window runs May 29 through June 19. time plantings around the expected last-frost window for best survival. A second sowing from July 2 to July 16 extends the harvest into fall.

When to Plant Leeks in Gunnison County, CO

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.

Gunnison County, Colorado is in USDA Zone 5a. The average last spring frost is June 12 and the first fall frost is September 10, giving you a growing season of approximately 90 days.

At an elevation of 7,435 feet, Gunnison County receives approximately 17.9 inches of rainfall annually with predominantly loam soil. Summer highs average 83°F, so choose short-season varieties of Leeks to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Leeks successfully. Mulch heavily to conserve soil moisture.

Gunnison County, CO (Zone 5a) Very short season
90 days
Last Spring Frost June 12
90 growing days
First Fall Frost September 10

Gunnison County Soil Profile

Soil Type

Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Leeks Planting Timeline — Gunnison County, CO

Leeks Planting Calendar

Activity When Date Range
Start Indoors May 8 May 8 – May 22
Transplant Outdoors June 12 Jun 12 – Jun 26
Direct Sow May 29 May 29 – Jun 19
Harvest September 11 Sep 11 – Nov 27
Fall Sowing July 2 Jul 2 – Jul 16

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

Month-by-Month Timeline

MonthActivities
January
February
March
April
May Start Indoors Direct Sow
June Transplant Outdoors Direct Sow
July Fall Sowing
August
September Harvest
October Harvest
November Harvest
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 5a

📆 Growing Season

90 days in Gunnison County

Growing Tips for Gunnison 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 Gunnison County, CO?

Gunnison County is in Zone 5a with an average last frost of June 12. Plan your Leeks planting based on this frost date — see the calendar above for exact timing.

What planting zone is Gunnison County, CO?

Gunnison County, Colorado is in USDA Hardiness Zone 5a. The average last spring frost is June 12 and first fall frost is September 10.

When should I plant Leeks in Gunnison County, CO?

In Gunnison County, CO, plant Leeks after the last frost (around June 12) and before the first frost (around September 10). Best results when soil holds above 50°F.

What growing zone is Gunnison County, CO for Leeks?

Gunnison County sits in USDA Zone 5a. Leeks grows reliably in zones 3a through 10b, so it's a good fit here.

Can Leeks grow in Gunnison County's climate?

Yes — Leeks grows well in Gunnison County's temperate climate. Gunnison County averages a 90-day frost-free season, with last frost around June 12 and first frost around September 10.

🌱

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A 22-page printable planner built for Gunnison County (Zone 5a). 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 Gunnison County, CO. Local conditions may vary. Last updated: June 2026.

Sources & credits

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