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When to Plant Onion in Lawrence County, OH

Onions are a fundamental kitchen staple available in yellow, white, and red varieties. Choose long-day, short-day, or intermediate types based on your latitude.

Lawrence County, Ohio is in USDA Zone 6b. The average last spring frost is April 23 and the first fall frost is October 21, giving you a growing season of approximately 181 days.

At an elevation of 1,332 feet, Lawrence County receives approximately 37.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89ยฐF, providing good warmth for Onion during the growing season.

Lawrence County, OH (Zone 6b) Moderate season
181 days
Last Spring Frost April 23
181 growing days
First Fall Frost October 21

Lawrence County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-7.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (46 days to spare)
Start indoors: Mar 10 Transplant: Apr 14 🍅 Harvest: Jul 14 – Sep 1
Recommended (50%) ✓ Fits season (41 days to spare)
Start indoors: Mar 19 Transplant: Apr 23 🍅 Harvest: Jul 23 – Sep 10
Safe Start (90%) ✓ Fits season (36 days to spare)
Start indoors: Apr 5 Transplant: May 10 🍅 Harvest: Aug 9 – Sep 27

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 Lawrence County

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

Soil pH

Your soil pH (5.8โ€“7.3) overlaps with Onion's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.8%) โ€” Onion will thrive.

How to Plant Onion

1"
Planting Depth
6"
Between Plants
12"
Between Rows

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 238 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Onion needs ~1,759 GDD — county provides 3,031 GDD Excellent fit

Onion Planting Timeline โ€” Lawrence County, OH

Onion 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
Fall Sowing August 12 Aug 12 โ€“ Aug 26
Harvest July 23 Jul 23 โ€“ Sep 10

Plant 1" deep ยท 6" apart ยท Rows 12" 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 โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

90โ€“120 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 6b

๐Ÿ“† Growing Season

181 days in Lawrence County

Growing Tips for Onion in Lawrence County

Direct sow Onion outdoors after April 23 in Lawrence County when soil has warmed and frost danger has passed.

Common pests for Onion 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 8-10 weeks before transplanting. Match day-length type to your latitude. Stop watering when tops begin to fall over and cure bulbs for 2-3 weeks before storage.

Companion Planting

Good Companions

Avoid Planting Near

  • Peas
  • Green Beans
  • Asparagus

Level Up Your Garden

Frequently Asked Questions

When should I plant Onion in Lawrence County, OH?

Lawrence County is in Zone 6b with an average last frost of April 23. Plan your Onion planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Lawrence County, OH?

Lawrence County, Ohio is in USDA Hardiness Zone 6b. The average last spring frost is April 23 and first fall frost is October 21.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Lawrence County gardeners in Zone 6b 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 Lawrence County, OH. Local conditions may vary. Last updated: April 2026.