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When to plant Leeks in Platte County County,

For Platte County County, gardeners: plant Leeks March 27 through April 17 once soil reads 50°F. A second sowing from August 17 to August 31 extends the harvest into fall.

When to Plant Leeks in Platte County, MO

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.

Platte County, Missouri is in USDA Zone 6b. The average last spring frost is April 10 and the first fall frost is October 26, giving you a growing season of approximately 199 days.

At an elevation of 1,021 feet, Platte County receives approximately 35.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Leeks during the growing season.

Platte County, MO (Zone 6b) Moderate season
199 days
Last Spring Frost April 10
199 growing days
First Fall Frost October 26

Platte County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-7

Drainage

Well Drained

Monthly Watering Guide for Leeks

Leeks needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Leeks Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 3.7" 0.6" 💧 Light watering
Jun 4.3" 4.3" 0" ✅ Rainfall sufficient
Jul 4.3" 4.4" 0" ✅ Rainfall sufficient
Aug 4.3" 4.1" 0.2" 💧 Light watering
Sep 4.3" 3.5" 0.8" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 2.4" 0" ❄️ Dormant
Dec 1.8" 0" ❄️ Dormant

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

Leeks Planting Timeline — Platte County, MO

Leeks Planting Calendar

Activity When Date Range
Start Indoors March 6 Mar 6 – Mar 20
Transplant Outdoors April 10 Apr 10 – Apr 24
Direct Sow March 27 Mar 27 – Apr 17
Harvest July 10 Jul 10 – Sep 25
Fall Sowing August 17 Aug 17 – Aug 31

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors Direct Sow
April Transplant Outdoors Direct Sow
May
June
July Harvest
August Fall Sowing Harvest
September Harvest
October
November
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 6b

📆 Growing Season

199 days in Platte County

Growing Tips for Platte 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 Platte County, MO?

Platte County is in Zone 6b with an average last frost of April 10. Plan your Leeks planting based on this frost date — see the calendar above for exact timing.

What planting zone is Platte County, MO?

Platte County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 10 and first fall frost is October 26.

When should I plant Leeks in Platte County County, ?

In Platte County County, , plant Leeks after the last frost (around April 10) and before the first frost (around October 26). Best results when soil holds above 50°F.

What growing zone is Platte County County, for Leeks?

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

Can Leeks grow in Platte County County's climate?

Yes — Leeks grows well in Platte County County's temperate climate. Platte County County averages a 199-day frost-free season, with last frost around April 10 and first frost around October 26.

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Your Platte County Garden Planner — Free

A 22-page printable planner built for Platte County (Zone 6b). 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 Platte County, MO. Local conditions may vary. Last updated: June 2026.

Sources & credits

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