Summer lettuce varieties are best planted in succession starting in mid-spring. Lettuces generally do not like heat, and tend to bolt. These lettuces that we offer are bred to be bolt-resistant under heat stress, though shadecloth will improve quality. Ben Shemen and Jericho were bred for heat-tolerance in the Negev desert. Our own Bronze Arrow is pretty darn heat tolerant as well. The others are heirlooms that have taken reasonable heat well, some over centuries of use.
Quick growth makes for good flavor and tenderness, so assure water and fertility. Lettuce seeds will not sprout once temperatures reach 85 F degrees. Putting seeds in a jar, in the refrigerator 4-5 days before planting will aid germination. In summer heat, sow in the evening, water well, and give some shade.
Lettuce types: Looseleafs make a head that fans out so that the center leaves are visible. They are tolerant of marginal conditions, and can be cut leaf-by-leaf or all at once.
Butterheads have a soft, silky texture and small, rose-like heads.
Bibbs are looser, with the same silky leaf, but a crunchy midrib.
Romaine (or Cos) makes a tall head with crunchy midrib.
Summercrisp types have a tall, ruffled head, with a crisp, somewhat blanched interior.
Iceberg types have a firm, wrapped head, and a dense, blanched, crisp interior.
Stem lettuce is a unique kind that is still good after bolting.
The leaves are widely eaten raw, but can also be boiled at a potherb, pickled, braised, sauteed, fried, pureed, and used in soups and stews. In the Middle East the bulghur wheat salad tabouli is wrapped in lettuce leaves and eaten out of hand. Sprouted seeds can be used in salads and sandwiches.
Fall varieties can be planted in pots or flats in a shady place in August, and transplanted into the garden under shade cloth or taller crops. Late fall crops of baby greens and a few ultra-hardy varieties can be planted September/October to stand through late fall, or winter in mild climates.