Cool days and chilly nights are just the kind of weather lettuce enjoys. Lettuce is easy to grow, and any gardener should consider it.
Because Louisiana summers are way too hot for lettuce, it’s a cool-season crop for us here, says LSU AgCenter horticulturist Dan Gill. January is a great time to plant seeds directly into the garden or in flats or pots to produce transplants.
Garden lettuces can be divided into three classes based on growth habit — leaf or loose-leaf types; semi-heading types, such as butterhead and romaine (or cos), and heading or crisp-head types.
Crisp-head lettuces, such as the iceberg types available in supermarkets, are more of a challenge to grow here, so Gill recommends staying with the leaf and semi-heading varieties.
“Leaf lettuces are the most decorative, least demanding and among the most heat-tolerant lettuces we can grow,” Gill says. They’re fast-maturing and can be ready to begin harvesting just 40 days after planting.
Gill recommends planting several crops in succession through the growing season for continued harvests.
Butterhead lettuces have soft, tender leaves and relatively loose heads that make them difficult to ship and pricey at the supermarket — but they’re quite easy to grow. Varieties to choose include bibb and buttercrunch, Gill says.
Romaine, or cos, lettuces are upright with thick smooth or ruffled leaves of red or green. They range in size from tiny 8-inch heads to large heads that can reach well over a foot tall.
You can generally find transplants and seeds in area nurseries and can plant them now through late March.
Plant seeds into well-prepared beds. Seeds need sunlight to germinate, so simply press or lightly rake them into the soil surface. Water them frequently until they germinate. And once they come up, thin them to about 10 inches between plants.
For best quality, lettuce must grow rapidly, so keep the plants well watered and fertilized. If temperatures are predicted below the mid-20s, throw a layer of pine straw or sheets of fabric over the plants to prevent frost burn.
Plant to complete harvest by early to mid-May because high temperatures will cause the lettuce to become increasingly bitter and bolt, sending up a flower stalk.
Got a gardening question? Write to GardenNews@agcenter.lsu.edu.