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When to Plant Leeks in Barton County, MO

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.

Barton County, Missouri is in USDA Zone 6a. The average last spring frost is April 9 and the first fall frost is October 26, giving you a growing season of approximately 200 days.

At an elevation of 1,165 feet, Barton County receives approximately 33.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89ยฐF, providing good warmth for Leeks during the growing season.

Barton County, MO (Zone 6a) Long season
200 days
Last Spring Frost April 9
200 growing days
First Fall Frost October 26

Barton County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (32 days to spare)
Start indoors: Feb 27 Transplant: Apr 3 🍅 Harvest: Jul 3 – Sep 18
Recommended (50%) ✓ Fits season (32 days to spare)
Start indoors: Mar 5 Transplant: Apr 9 🍅 Harvest: Jul 9 – Sep 24
Safe Start (90%) ✓ Fits season (34 days to spare)
Start indoors: Mar 17 Transplant: Apr 21 🍅 Harvest: Jul 21 – Oct 6

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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 528 gal / 100 sq ft
Leeks needs ~2,010 GDD — county provides 3,350 GDD Excellent fit

Leeks Planting Timeline โ€” Barton County, MO

Leeks Planting Calendar

Activity When Date Range
Start Indoors March 5 Mar 5 โ€“ Mar 19
Transplant Outdoors April 9 Apr 9 โ€“ Apr 23
Direct Sow March 26 Mar 26 โ€“ Apr 16
Fall Sowing August 17 Aug 17 โ€“ Aug 31
Harvest July 9 Jul 9 โ€“ Sep 24

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

90โ€“150 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 6a

Growing Season

200 days

Growing Tips for Barton 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

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Frequently Asked Questions

When should I plant Leeks in Barton County, MO?

Barton County is in Zone 6a with an average last frost of April 9. Plan your Leeks planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Barton County, MO?

Barton County, Missouri is in USDA Hardiness Zone 6a. The average last spring frost is April 9 and first fall frost is October 26.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Barton County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.

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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 Barton County, MO. Local conditions may vary. Last updated: April 2026.