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When to Plant Lettuce in USDA Zone 3b

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.

In Zone 3b, the average last spring frost is around May 10 and the first fall frost is around September 22, giving you a growing season of approximately 135 days.

Zone 3b Short season
135 days
Last Spring Frost May 10
135 growing days
First Fall Frost September 22

Lettuce Planting Timeline — Zone 3b

Where Is USDA Zone 3b?

The map below highlights the states that contain Zone 3b. Click any state to see the Lettuce planting schedule for that location.

Prints a clean, ink-friendly version without maps or navigation.

Lettuce Planting Calendar — Zone 3b

Activity When Date Range
Start Indoors March 29 Mar 29 – Apr 12
Transplant Outdoors May 10 May 10 – May 24
Direct Sow May 3 May 3 – May 24
Harvest June 14 Jun 14 – Aug 23
Fall Sowing June 30 Jun 30 – Jul 14

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

Month-by-Month Timeline

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

Free Zone 3b Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 3b with start dates, transplant windows, and harvest times.

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Growing Conditions

Sun

Partial Shade (3-6 hours)

💧 Water

0.7"/week · Moderate — regular watering

Days to Maturity

30–60 days

Soil pH

6 – 7

Zone Temperature Range

-35°F to -30°F average annual minimum

Growing Season

135 days (Zone 3b average)

Planting Specifications

Planting Depth0.5 inches
Plant Spacing6 inches apart
Row Spacing12 inches between rows

Succession Planting Lettuce in Zone 3b

5
successive plantings in Zone 3b's ~135-day season

Sow every 3.4 weeks for continuous harvest throughout the season.

Growing Tips for Lettuce in Zone 3b

Zone 3b has a short growing season (~135 days). Start Lettuce indoors early and use season-extension techniques like row covers and cold frames.

Lettuce needs approximately 0.7 inches of water per week during active growth. Adjust watering based on your local rainfall and soil drainage.

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.

Companion Planting

Good Companions

Avoid Planting Near

  • Celery

Level Up Your Garden

Saving Lettuce Seeds

🌾 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.

Recommended for Your Garden

💡
LED Grow Lights $25-60

Full-spectrum LED lights for starting seeds indoors when daylight is limited.

🔥
Seedling Heat Mat $15-35

Warm soil for faster germination of heat-loving crops like tomatoes and peppers.

🪡
Floating Row Covers $12-30

Protect plants from frost, wind, and pests while letting light and water through.

Related Plants

Frequently Asked Questions

When should I plant Lettuce in Zone 3b?

In Zone 3b, plan your Lettuce planting around the average last frost date of May 10. Start seeds indoors around March 29. Direct sow outdoors around May 3. Transplant seedlings around May 10.

Can Lettuce grow in Zone 3b?

Yes, Lettuce can grow well in Zone 3b, hardy in USDA zones 2a through 11b. Zone 3b has a growing season of approximately 135 days, which is sufficient for Lettuce (30-60 days to maturity).

When can I harvest Lettuce in Zone 3b?

In Zone 3b, expect to harvest Lettuce from June 14 – August 23. Lettuce takes 30-60 days from planting to harvest.

What is the last frost date for Zone 3b?

The average last spring frost in Zone 3b is around May 10, and the first fall frost is around September 22. This gives a growing season of approximately 135 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Lettuce?

Good companion plants for Lettuce include Carrots, Radish, Chives, Onion. These companions can help with pest control, pollination, and nutrient sharing.

🌱

Plan Your Garden with Confidence

Get our free Garden Planner — organize your planting dates for Zone 3b, track your crops, and plan your garden season from seed to harvest.

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, University Cooperative Extension planting guides. Planting dates are estimates based on average frost dates — local conditions may vary. Last updated: April 2026.