Latuca sativa is a member of the Asteraceae (sunflower) family.

Varieties include: Butterhead types, also called Bibb (an open, loose head with green outer leaves and yellow inner leaves, such as Boston): Merveille de Quatre Saison, Red Perella, Tom Thumb, Buttercrunch, Red Riding Hood, Esmeralda.

Leaf (has a loose rosette of leaves. This type tolerates heat better than other types and is a summer mainstay in warm weather areas): Red Sails, Red Salad Bowl, Waldmans Green, Flame, Green or Red Oakleaf, Lolla Rossa, Royal Red.

Romaine or Cos (tall, slender, upright head. Withstands heat moderately well. Higher in vitamin A and C than other types.): Rouge d'Hiver (good as a baby), Sucrine, Valmaine, Green Towers.

Batavian (generally forms a softer, looser head than the butterhead types but still has a crunchy, juicy texture): Cybele Batavian, Dorée de Printemps, Reine des Glaces.

Crisphead or Iceberg (this is not a specialty lettuce, it is the familiar supermarket type with a tight, firm ball. It is included here for information purposes.): Great Lakes or Vanguard types.

Light green - White Boston

Medium green - Buttercrunch

Dark Green - Dark Green Boston

Yellow green - Black Seeded Simpson

Full light red - De Morges Braun

Full medium red - Red Sails

Full dark red - Ruby

Red tinge - Brune d'Hiver

Bronzy red tinge - Antina

Tinge is a red color on the leaf margins such as with Prizehead or Antina. Full red means an overall red coloration such as with Merveille des Quatres Saisons even though the inner leaves are a light bright green. All full reds still have green interiors which is desired by the buyers.

Growth habit. Fancy lettuces now available in every green-red combination in every type of head. Lettuce is native to the Eastern Mediterranean area.

Marketing. Specialty lettuce should be marketed as baby or mid-size, there is a very limited market for full size specialty lettuce. As a "baby" it can be packed in an LA lug or similar size box with 48 to 72 heads packed snug. For a nice looking box pack with 4 varieties, half green and half red. Keep them wet and cold. They are often packed in a poly bag in the box.

Use. In salads for color, flavor, shape, and texture.

Nutrition. Good sources of fiber and potassium. Romaine and leaf contain about 40 percent of the RDA for vitamin A in a 3 and a half ounce serving.

Climatic requirements. Climate is the major influence on lettuce. Lettuce grows best as a cool-season crop with 70-75°F being ideal. Long, warm summer days cause most varieties to bolt (go to seed), leaving the plants tough, bitter and unusable.

Propagation and care. In central California coastal areas, plant February and March or August and September from seed, for most varieties. In southern California inland valleys and low desert areas seed from early September through early November. In southern coastal areas seed from September through February. In the Sacramento Valley, plant September and October. October planted lettuce will hold all winter long through January.

Lettuce should be planted half an inch apart in rows 10 to 20 inches apart and thinned to 8 inches to 14 inches apart in the row depending on the type. The seed should be planted no deeper than one quarter inch. Germination takes 7 to 10 days. Lettuce can also be grown as transplants and placed in the field at 30 to 40 days after emergence. Thin plants which are direct seeded when they have 2 to 3 true leaves. Lettuce needs an ample supply of nitrogen and phosphorus and regular irrigations. Lettuce may be harvested anytime. Some cooks make salads from extra small lettuce plants removed during thinning.

Lettuce grown as baby lettuce is most commonly planted close together in raised beds.

Harvest and postharvest practices. Store at 34°F with 90-95 percent relative humidity. Air circulation is important. Stagger stacking, no more than two layers deep, to attain maximum circulation.

W. Atlee Burpee & Co., 300 Park Avenue, Warmister, PA 18974.
The Cook's Garden, P.O. Box 65, Londonderry, VT 05148
Johnny's Selected Seeds, Foss Hill Rd., Albion, Maine 04910.
Nichols Garden Nursery, 1190 North Pacific Hwy, Albany, OR 97321.

Ornamental Edibles, 3622 Weedin Court, San Jose, CA 95132.
Park Seed Co., Cokesbury Road, Greenwood, SC 29647-0001.
Seeds Blum, Idaho City Stage, Boise, ID 83706.
Shepherd's Garden Seeds, Shipping Office, 30 Irene Street, Torrington, Conn. 06790.

Stokes Seeds, P.O. Box 548, Buffalo, NY 14240.

Abundant Life Seed Foundation, P.O. Box 772, Port Townshend, WA 98368.

Le Jardin du Gourmet, P. O. Box 75, St. Johnsbury Center, VT 05863.

Reviewed by Martin Barnes, March 1989.

Reviewed by Vince Rubatzky, March 1989.

Reviewed by Hunter Johnson, Oct 1989.

Reviewed by David Visher, 12/89

Compiled by Nancy Garrison, Wes Foster, Claudia Myers and Keith Mayberry, Santa Clara County Farm Advisor, UC Master Gardener, UC Small Farm Center, and Imperial County Farm Advisor, respectively.

Captions:

Figure 1. Numerous baby lettuce varieties being grown in raised beds at Kona Kai Farms in Berkeley. (Photo by Charlotte Glenn).

Figure 2. Lolla Rossa is a beautiful red leaf lettuce variety. (Photo by Charlotte Glenn).

Figure 3. Green oakleaf lettuce. (Photo by Charlotte Glenn).

3/16/90