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When to Plant Lettuce in Preble County, OH

Preble County, Ohio Zone 6a May

This month in Preble County, Ohio

A quick May briefing for Preble County, Ohio gardeners — what's urgent, what's next, and what can wait.

Avg. last frost April 24
Avg. first frost October 21
Soil temp (4") 62°F
Watering Low
Pest pressure Low
Daylight 14.2 hrs
  1. Indoor seed-starting week for lettuce

    Give them 6–8 weeks indoors before the last frost and you'll transplant into warm soil with seedlings that are already leaping.

  2. Bring in the lettuce

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

To set up a strong June, finish these tasks
  • First harvests: lettuce

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Lettuce is a fast-growing cool-season green available in leaf, romaine, butterhead, and crisphead types. It is the foundation of salads and one of the easiest crops to grow.

Preble County, Ohio is in USDA Zone 6a. The average last spring frost is April 24 and the first fall frost is October 21, giving you a growing season of approximately 180 days.

At an elevation of 1,250 feet, Preble County receives approximately 40 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Lettuce during the growing season.

Preble County, OH (Zone 6a) Moderate season
180 days
Last Spring Frost April 24
180 growing days
First Fall Frost October 21
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Preble County Soil Profile

Soil Type

Silt Loam

Soil pH

6-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (76 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: May 20 – Jul 29
Recommended (50%) ✓ Fits season (75 days to spare)
Start indoors: Mar 20 Transplant: Apr 24 🍅 Harvest: May 29 – Aug 7
Safe Start (90%) ✓ Fits season (73 days to spare)
Start indoors: Apr 4 Transplant: May 9 🍅 Harvest: Jun 13 – Aug 22

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 Preble County

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

Soil pH

Your soil pH (6.0–6.9) is within Lettuce's preferred range (6.0–7.0).

Soil Texture

The silt loam soil in Preble County is excellent for Lettuce — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.9%). Annual compost additions will help Lettuce.

How to Plant Lettuce

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

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

Succession Planting Lettuce

7
successive plantings in your 180-day season

Sow every 3.4 weeks. Last sowing by Aug 22 to harvest before frost.

For a dedicated fall crop, sow by Aug 12.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Lettuce

Lettuce needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Lettuce Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 1.9" 0" ❄️ Dormant
Mar 2.8" 0" ❄️ Dormant
Apr 3" 4.1" 0" ✅ Rainfall sufficient
May 3" 4.5" 0" ✅ Rainfall sufficient
Jun 3" 4.7" 0" ✅ Rainfall sufficient
Jul 3" 4.9" 0" ✅ Rainfall sufficient
Aug 3" 3.9" 0" ✅ Rainfall sufficient
Sep 3" 3.1" 0" ✅ Rainfall sufficient
Oct 3" 3.1" 0" ✅ Rainfall sufficient
Nov 3" 0" ❄️ Dormant
Dec 2.3" 0" ❄️ Dormant

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

Lettuce Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Lettuce needs ~821 GDD — county provides 3,285 GDD Excellent fit

Lettuce Planting Timeline — Preble County, OH

Lettuce Planting Calendar

Activity When Date Range
Start Indoors March 20 Mar 20 – Apr 3
Transplant Outdoors April 24 Apr 24 – May 8
Direct Sow April 10 Apr 10 – May 1
Harvest May 29 May 29 – Aug 7
Fall Sowing August 12 Aug 12 – Aug 26

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

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

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.7"/week · Natural rainfall sufficient

📅 Days to Maturity

30–60 days

🧪 Soil pH

Needs 6–7 · Your soil: ideal

🗺️ USDA Zone

Zone 6a

📆 Growing Season

180 days in Preble County

Growing Tips for Lettuce in Preble County

Direct sow Lettuce outdoors after April 24 in Preble County when soil has warmed and frost danger has passed.

Summer highs in Preble County reach 91°F — grow Lettuce as a spring or fall crop. Use shade cloth if planting in summer.

Your generous 180.0-day season in Preble County allows multiple plantings of Lettuce. Sow every 15.0 days for continuous harvest.

Common pests for Lettuce in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

Sow seeds directly every 2 weeks for continuous harvest. Provide afternoon shade in warm weather to delay bolting. Harvest in the morning for crispest leaves.

Recommended Lettuce Varieties for Preble County

Bolt-resistant varieties for warm summers — grow as spring/fall crop

Jericho Muir Nevada New Red Fire

Companion Planting

Good Companions

Avoid Planting Near

  • Celery

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Lettuce Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Let plants bolt and flower. Harvest seed heads when fluffy.
Storage Store airtight; viable 6 years at 35°F, under 45% humidity.

Very easy to save. Let a few plants bolt each season.

Frequently Asked Questions

When should I plant Lettuce in Preble County, OH?

Preble County is in Zone 6a with an average last frost of April 24. Plan your Lettuce planting based on this frost date — see the calendar above for exact timing.

What planting zone is Preble County, OH?

Preble County, Ohio is in USDA Hardiness Zone 6a. The average last spring frost is April 24 and first fall frost is October 21.

🌱

Your Preble County Garden Planner — Free

A 24-page printable planner built for Preble County (Zone 6a). 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 Preble County, OH. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.