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When to Plant Lettuce in Hunterdon County, NJ

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.

Hunterdon County, New Jersey is in USDA Zone 6b. The average last spring frost is April 12 and the first fall frost is October 29, giving you a growing season of approximately 200 days.

At an elevation of 534 feet, Hunterdon County receives approximately 46.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90ยฐF, providing good warmth for Lettuce during the growing season.

Hunterdon County, NJ (Zone 6b) Long season
200 days
Last Spring Frost April 12
200 growing days
First Fall Frost October 29

Hunterdon County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (91 days to spare)
Start indoors: Mar 1 Transplant: Apr 5 🍅 Harvest: May 10 – Jul 19
Recommended (50%) ✓ Fits season (95 days to spare)
Start indoors: Mar 8 Transplant: Apr 12 🍅 Harvest: May 17 – Jul 26
Safe Start (90%) ✓ Fits season (90 days to spare)
Start indoors: Mar 27 Transplant: May 1 🍅 Harvest: Jun 5 – Aug 14

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 Hunterdon County

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

Soil pH

Your soil pH (5.2โ€“6.3) is more acidic than Lettuce prefers (6.0โ€“7.0). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.7%). 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

8
successive plantings in your 200-day season

Sow every 3.4 weeks. Last sowing by Aug 30 to harvest before frost.

For a dedicated fall crop, sow by Aug 20.

Plant Water Budget

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

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 โ€” 3.7" 0" โ„๏ธ Dormant
Feb โ€” 2.7" 0" โ„๏ธ Dormant
Mar โ€” 4.1" 0" โ„๏ธ Dormant
Apr 3" 3.8" 0" โœ… Rainfall sufficient
May 3" 3.7" 0" โœ… Rainfall sufficient
Jun 3" 4.1" 0" โœ… Rainfall sufficient
Jul 3" 5.1" 0" โœ… Rainfall sufficient
Aug 3" 4.1" 0" โœ… Rainfall sufficient
Sep 3" 4.1" 0" โœ… Rainfall sufficient
Oct 3" 4.1" 0" โœ… Rainfall sufficient
Nov โ€” 3.7" 0" โ„๏ธ Dormant
Dec โ€” 3.5" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Hunterdon County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 ~788 GDD — county provides 3,500 GDD Excellent fit

Lettuce Planting Timeline โ€” Hunterdon County, NJ

Lettuce Planting Calendar

Activity When Date Range
Start Indoors March 8 Mar 8 โ€“ Mar 22
Transplant Outdoors April 12 Apr 12 โ€“ Apr 26
Direct Sow March 29 Mar 29 โ€“ Apr 19
Harvest May 17 May 17 โ€“ Jul 26
Fall Sowing August 20 Aug 20 โ€“ Sep 3

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

0.7"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

30โ€“60 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 6b

๐Ÿ“† Growing Season

200 days in Hunterdon County

Growing Tips for Lettuce in Hunterdon County

Direct sow Lettuce outdoors after April 12 in Hunterdon County when soil has warmed and frost danger has passed.

Your generous 200.0-day season in Hunterdon 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 Hunterdon County

Bolt-resistant varieties for warm summers โ€” 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 →

๐ŸŒพ 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 35ยฐF, under 45% humidity.

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

Frequently Asked Questions

When should I plant Lettuce in Hunterdon County, NJ?

Hunterdon County is in Zone 6b with an average last frost of April 12. Plan your Lettuce planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Hunterdon County, NJ?

Hunterdon County, New Jersey is in USDA Hardiness Zone 6b. The average last spring frost is April 12 and first fall frost is October 29.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Hunterdon 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 Hunterdon County, NJ. Local conditions may vary. Last updated: April 2026.