Blog

When to Plant Leeks in Putnam County, OH

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.

Putnam County, Ohio is in USDA Zone 5b. The average last spring frost is April 23 and the first fall frost is October 22, giving you a growing season of approximately 182 days.

At an elevation of 1,300 feet, Putnam County receives approximately 40.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Leeks to ensure they mature before fall.

Putnam County, OH (Zone 5b) Moderate season
182 days
Last Spring Frost April 23
182 growing days
First Fall Frost October 22

Putnam County Soil Profile

Soil Type

Silt Loam

Soil pH

6.3-6.7

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 โ€” 1.8" 0" โ„๏ธ Dormant
Feb โ€” 1.7" 0" โ„๏ธ Dormant
Mar โ€” 2.9" 0" โ„๏ธ Dormant
Apr 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
May 4.3" 4.8" 0" โœ… Rainfall sufficient
Jun 4.3" 4.2" 0.1" ๐Ÿ’ง Light watering
Jul 4.3" 4.9" 0" โœ… Rainfall sufficient
Aug 4.3" 4.6" 0" โœ… Rainfall sufficient
Sep 4.3" 3.9" 0.4" ๐Ÿ’ง Light watering
Oct 4.3" 2.9" 1.4" ๐Ÿ’ง Light watering
Nov โ€” 2.6" 0" โ„๏ธ Dormant
Dec โ€” 2.2" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Putnam County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Leeks Planting Timeline โ€” Putnam County, OH

Leeks Planting Calendar

Activity When Date Range
Start Indoors March 19 Mar 19 โ€“ Apr 2
Transplant Outdoors April 23 Apr 23 โ€“ May 7
Direct Sow April 9 Apr 9 โ€“ Apr 30
Harvest July 23 Jul 23 โ€“ Oct 8
Fall Sowing August 13 Aug 13 โ€“ Aug 27

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

Moderate โ€” regular watering

๐Ÿ“… Days to Maturity

90โ€“150 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: N/A

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

182 days in Putnam County

Growing Tips for Putnam 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 Putnam County, OH?

Putnam County is in Zone 5b with an average last frost of April 23. Plan your Leeks planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Putnam County, OH?

Putnam County, Ohio is in USDA Hardiness Zone 5b. The average last spring frost is April 23 and first fall frost is October 22.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Putnam County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Putnam County, OH. Local conditions may vary. Last updated: April 2026.