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When to Plant Lettuce in Miami-Dade County, FL

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.

Miami-Dade County, Florida is in USDA Zone 10b. The average last spring frost is January 1 and the first fall frost is December 31, giving you a growing season of approximately 364 days.

At an elevation of 123 feet, Miami-Dade County receives approximately 58.7 inches of rainfall annually with predominantly sand soil. Summer highs average 90ยฐF, providing good warmth for Lettuce during the growing season. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Lettuce will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Lettuce root diseases.

Miami-Dade County, FL (Zone 10b) Year-round
364 days
Last Spring Frost January 1
364 growing days
First Fall Frost December 31

Miami-Dade County Soil Profile

Soil Type

Sand

Soil pH

5.1-6.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (78 days to spare)
Start indoors: Mar 18 Transplant: Apr 15 🍅 Harvest: May 20 – Jul 29
Recommended (50%) ✓ Fits season (78 days to spare)
Start indoors: Mar 18 Transplant: Apr 15 🍅 Harvest: May 20 – Jul 29
Safe Start (90%) ✓ Fits season (78 days to spare)
Start indoors: Mar 18 Transplant: Apr 15 🍅 Harvest: May 20 – Jul 29

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 Miami-Dade County

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

Soil pH

Your soil pH (5.1โ€“6.3) is more acidic than Lettuce prefers (6.0โ€“7.0). Add garden lime to raise pH.

Soil Texture

Sandy soil in Miami-Dade County warms quickly in spring but drains fast. Lettuce will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Lettuce.

Organic Matter

Organic matter is low (1.3%). Add 2-3 inches of compost before planting Lettuce.

How to Plant Lettuce

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

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.7″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 762 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 3" 2.9" 0.1" ๐Ÿ’ง Light watering
Feb 3" 2.9" 0.1" ๐Ÿ’ง Light watering
Mar 3" 3.4" 0" โœ… Rainfall sufficient
Apr 3" 2.5" 0.5" ๐Ÿ’ง Light watering
May 3" 3.8" 0" โœ… Rainfall sufficient
Jun 3" 8.1" 0" โœ… Rainfall sufficient
Jul 3" 9.5" 0" โœ… Rainfall sufficient
Aug 3" 8.6" 0" โœ… Rainfall sufficient
Sep 3" 7.1" 0" โœ… Rainfall sufficient
Oct 3" 5" 0" โœ… Rainfall sufficient
Nov 3" 2.3" 0.7" ๐Ÿ’ง Light watering
Dec 3" 2.7" 0.3" ๐Ÿ’ง Light watering

Water needs are for active growing months only (Janโ€“Dec in Miami-Dade 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 6,387 GDD Excellent fit

Lettuce Planting Timeline โ€” Miami-Dade County, FL

Lettuce Planting Calendar

Activity When Date Range
Start Indoors December 4 Dec 4 โ€“ Dec 18
Transplant Outdoors January 1 Jan 1 โ€“ Jan 15
Direct Sow December 11 Dec 11 โ€“ Jan 1
Harvest February 5 Feb 5 โ€“ Apr 16
Fall Sowing November 5 Nov 5 โ€“ Nov 19

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

0.7"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

30โ€“60 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 10b

๐Ÿ“† Growing Season

364 days in Miami-Dade County

Growing Tips for Lettuce in Miami-Dade County

Sandy soil in Miami-Dade County dries quickly โ€” mulch Lettuce with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

Your generous 365.0-day season in Miami-Dade 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 Miami-Dade 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 Miami-Dade County, FL?

Miami-Dade County is in Zone 10b with an average last frost of January 1. Plan your Lettuce planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Miami-Dade County, FL?

Miami-Dade County, Florida is in USDA Hardiness Zone 10b. The average last spring frost is January 1 and first fall frost is December 31.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Miami-Dade County gardeners in Zone 10b 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 Miami-Dade County, FL. Local conditions may vary. Last updated: April 2026.