Lettuce is one vegetable that can be grown in Florida. For a fraction of the price of grocery store bagged lettuces, you can grow gourmet varieties throughout spring, fall and most of winter. Fresh-picked lettuce is higher in nutrients than lettuce that's been in transit to stores for several days. If you grow it organically, you don't need to worry about any pesticide residues on your lettuce.
Starting Lettuce from Seed in Florida
Select seeds recommended by the University of Florida Institute of Food and Agriculture. All types of lettuce, such as loose leaf, Cos or romaine, crisphead, butterhead and stem, can be grown in Florida. Seed varieties to consider are crisphead: Great Lakes; butterhead: Ermosa, Bibb, Tom Thumb and Buttercrunch; loose leaf, Simpson types; Salad Bowl, Red Sails and New Red Fire; oak leaf: Salad Bowl and Royal Oak; and romaine: Parris Island Cos and Outredgeous.
Increase fertility and drainage in your soil by digging in 6 inches of composted cow manure. Most Florida soils are either sand- or clay-based. The addition of compost will benefit both soil types. Hoe or till soil to a fine tilth. Cover soil with straw and wait three to six weeks after amending soil before planting. This will allow pH levels to stabilize.
Establish an irrigation system. Sprinklers are an effective irrigation method prior to germination. Drip irrigation uses less water after irrigation. Drip irrigation is not subject to water restriction regulations in many Florida counties. Sprinkler and drip irrigation reduce salinity buildup in garden soil.
Remove straw and dampen soil with water before sowing seeds. Broadcast leaf lettuce seeds in rows 1 to 2 feet apart in 12-inch-wide beds. Broadcast head lettuce seeds in rows 3 feet apart in 12-inch-wide beds. Lettuce seeds are too tiny to space. After germination, thin leaf lettuce plants 6 to 10 inches apart and head lettuce plants 12 inches apart. For a continuous supply of lettuce, successive sow every three weeks.
Maintaining Lettuce Plants in Florida
Add 1 to 2 inches of compost and mulch around the plants with straw two weeks after germination. If you live in an area where slugs are prevalent, don't mulch with straw. Instead, surround young lettuce plants with thin strips of copper or cut the tops and bottoms from 1-liter soda bottles and use these as collars around each plant.
Hoe or hand-pull weeds as soon as they appear. Weed competition reduces plant vigor, provides shelter for pests and encourages diseases. Lettuce is a shallow-rooted plant. so don't disturb the roots when hoeing.
Water lettuce plants thoroughly. To discourage moisture-related disease and some pests, water in the morning so the plants can dry before nighttime temperatures drop. Water until the soil is moist 6 inches below the surface. Consistent moisture levels are critical for lettuce head development.
Harvest leaf lettuce 70 to 75 days after planting or when plants are approximately 6 inches tall. Harvest head lettuce 55 days after planting or when the leaves overlap each other and form a round head. Bibb lettuce is ready to harvest when the leaves cup inward and form a loose head. Cos and romaine lettuce are mature when the leaves are 6 to 8 inches long and form a long, tight head.