There are many benefits to living in warm climates. However, having fresh lettuce in the garden past mid to late spring may not be one of the benefits most gardeners think of. Lettuce (Lactuca sativa) typically prefers to grow where the temperatures stay a bit cooler.
The heat of early summer can cause plants to go to seed early which turns the normally sweet leaves, bitter. This tendency of lettuce (referred to as bolting) may cause many who garden in warm climates to leave it off their garden seed list. It does not have to be this way though. By choosing heat tolerant varieties which have stood the test of time, any gardener can grow lettuce in the backyard vegetable garden.
Unlike many heirloom seed varieties, lettuce heirlooms are readily available. There are many varieties making certain that every gardener can find those which will thrive in their area.
One problem with growing lettuce is getting it into the ground early enough to germinate and allow harvesting before the heat of summer becomes too intense. Planting heat tolerant varieties will help by allowing for a longer harvest season before plants go to seed.
Heat Tolerant Lettuce Varieties
Heirloom lettuces which can take a bit more heat than their near cousins are listed below.
- Buttercrunch is a bibb-type lettuce with a tight center rosette and dark green leaves.
- Brown Mignonette is a butterhead lettuce which produces small, flavorful, compact heads early in the season. Edges of leaves have a dark green to red-brown coloring. This is a good variety for those with small gardens.
- Merveille de Quatre Saisons is a bibb-type lettuce with a compact green heart and reddish-purple tipped leaves.
- New York Head is an iceberg-type heading lettuce which grows very large possibly reaching four pounds. It is very sweet and tolerates heat and cold equally well.
- Oak Leaf lettuce is a loose-leaf variety with both green and red leaves. Growing this variety will add color plenty of to spring and summer salads. This is a dependable ‘cut-and-come-again’ plant.
- Red Romaine lettuce or cos is a leafy lettuce with a crisp texture which grows on stalks rather than close to the ground like other leaf lettuce. Like its name suggests, red romaine has red leaves.
- Rouge De Grenoblouse is an extremely bolt-resistant crisphead lettuce. It has a very sweet flavor even when grown in hot climates.
- Rouge De Hiver or Rouge d’Hiver is a romaine lettuce with sweet, buttery flavor. It has very large leaves and is dependable in the heat.
- Simpson Black Seeded lettuce is a loose-leaf variety with light green curly leaves. This is the old time favorite most gardeners have heard of. It matures early and is also a good ‘cut-and-come-again’ lettuce.
- White Boston is a butterhead lettuce which produces light green heads with a creamy-yellow heart. Heads are firm, round and approximately twelve inches. It is extremely heat-tolerant and recommended for Florida gardens.
Prolong Lettuce Harvest
Extending the salad season is as easy as planting leaf lettuce in containers on a patio. If placed where they receive a bit of afternoon shade in the hottest part of the summer, another cutting or two may be possible.