Blog

When to Plant Leeks in Johnson County, AR

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.

Johnson County, Arkansas is in USDA Zone 7a. The average last spring frost is March 26 and the first fall frost is November 3, giving you a growing season of approximately 222 days.

At an elevation of 1,347 feet, Johnson County receives approximately 49.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91ยฐF, providing good warmth for Leeks during the growing season.

Johnson County, AR (Zone 7a) Long season
222 days
Last Spring Frost March 26
222 growing days
First Fall Frost November 3

Johnson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (53 days to spare)
Start indoors: Feb 14 Transplant: Mar 21 🍅 Harvest: Jun 20 – Sep 5
Recommended (50%) ✓ Fits season (54 days to spare)
Start indoors: Feb 19 Transplant: Mar 26 🍅 Harvest: Jun 25 – Sep 10
Safe Start (90%) ✓ Fits season (61 days to spare)
Start indoors: Mar 5 Transplant: Apr 9 🍅 Harvest: Jul 9 – Sep 24

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 Johnson County

How your county's soil matches Leeks's growing requirements.

Soil pH

Your soil pH (5.3โ€“7.0) overlaps with Leeks's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

The silt loam soil in Johnson County is excellent for Leeks โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.6%). Annual compost additions will help Leeks.

How to Plant Leeks

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Leeks needs ~2,190 GDD — county provides 4,051 GDD Excellent fit

Leeks Planting Timeline โ€” Johnson County, AR

Leeks Planting Calendar

Activity When Date Range
Start Indoors February 19 Feb 19 โ€“ Mar 5
Transplant Outdoors March 26 Mar 26 โ€“ Apr 9
Direct Sow March 12 Mar 12 โ€“ Apr 2
Fall Sowing August 25 Aug 25 โ€“ Sep 8
Harvest June 25 Jun 25 โ€“ Sep 10

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.8"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

90โ€“150 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

222 days in Johnson County

Growing Tips for Leeks in Johnson County

Direct sow Leeks outdoors after March 26 in Johnson County when soil has warmed and frost danger has passed.

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

  • Peas
  • Green Beans

Level Up Your Garden

Frequently Asked Questions

When should I plant Leeks in Johnson County, AR?

Johnson County is in Zone 7a with an average last frost of March 26. Plan your Leeks planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Johnson County, AR?

Johnson County, Arkansas is in USDA Hardiness Zone 7a. The average last spring frost is March 26 and first fall frost is November 3.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Johnson County gardeners in Zone 7a 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 Johnson County, AR. Local conditions may vary. Last updated: April 2026.