Lettuce us introduce you to a great salad

The foundation of any vegetable garden is lettuce (Lactuca sativa), which is from the Asteraceae or daisy family. Easy to grow and quick to harvest, there are hundreds of varieties available to gardeners.

The leafy or nonheading types of lettuce are most often used as greens. This includes varieties of bibb, romaine, leaf, and Batavian lettuces:

Bibb lettuce has a whorl of open/semiopen leaves with a very dense, almost romainelike heart.

Butterhead or Boston lettuce forms a semi-dense ball. The leaves are less crisp than bibbs and have a wonderful buttery texture. They reach full size about eight to 10 weeks after planting.

'Buttercrunch' is a long-time favorite and 1963 All-America Selections winner. The compact heads produce delicious, green leaves that can be harvested when small and served as an individual-sized salad.

Even smaller is 'Tom Thumb,' a crisp and sweet butterhead about the size of a tennis ball. This is an ideal variety for growing in containers or for gardeners with very limited space.

The French heirloom 'Marveille de Quatre Saisons' lettuce is one of the earliest to harvest and has outer leaves of reddish brown with cranberry red edges and a creamy yellow center.

Cos or romaine lettuce has large, green, wrinkled leaves with a nice crisp texture and flavor. The oblong leaves grow upright and form loose, cone-shaped heads. It is the essential ingredient for a traditional Caesar salad. Romaines take a little longer to reach full size than other types of lettuces, generally nine to 10 weeks after planting, but they are also more heat-tolerant.

'Parris Island Cos' is a standard romaine with crinkled, medium green leaves that form a large tight head. It resists tip burn and is slow to bolt.

'Little Gem' is an heirloom variety with tight green leaves that are sweet and crunchy. These small plants are delicious when cut at five to seven inches tall.

'Rouge d'Hiver' or Red Winter is another heirloom popular for the nicely sized heads of reddish-bronze leaves that stay crisp after harvest. It is very tolerant of both hot and cold temperatures, making it ideal for any garden.

Leaf lettuce provides a quick harvest and comes in a variety of colors, shapes, and textures. Seed racks and catalogs are filled with so many varieties it may be hard to choose which one to grow.

Fortunately, a lot of lettuce can be produced from a small row or even in a container, so there's probably room to plant more than one variety. Or choose one of the many custom lettuce blends created by seed companies. These mixes are a great way to sample many different lettuces from a single packet.

Lettuces are very easy to grow and produce vigorously until summer's heat. Leaves come in shades of green and red ranging from light lime green to deep wine red. They can be harvested at almost any size, but most reach full size 40 to 50 days after planting.

Leaf lettuces are also popular as cut-and-come-again lettuces. When the leaves are mature, harvest the whole plant, just make sure to cut above the growing point so that the plant will grow back to provide a second harvest of tasty leaves.

'Black Seeded Simpson' continues to be one of the most popular leaf lettuces. It's prized for its large, light-green, crinkled leaves and its tolerance of drought, heat, and frost. It is also slow to bolt (got to seed in hot weather) so leaves can be picked over a long harvest period.

'Red Sails' is a 1985 All-America Selections winner that has soft, buttery leaves ruffled and edged with burgundy.

The darkest of lettuces, 'Merlot,' forms loose heads of sweet red leaves that appear almost purple.

'Speckles' is a European heirloom with green leaves spattered with red to add lovely color to any salad or mix of greens.

For fullness and texture, add the frilly-leaved 'Lolla (or Lollo) Rossa' with green leaves edged with red.

All of these leaf lettuces make an attractive edible ornamental for edging borders and filling containers. The foliage can even be used to add color and texture to the flower garden.

Summercrisp lettuce, also known as Batavian lettuce, is not as common in American gardens as other types of lettuce. However, it's a wonderful green with a nice crisp texture and sweet flavor.

Batavian lettuce plants are like leaf lettuce when young but as they mature, they begin to form larger heads that are ready to harvest in 50 to 60 days. They have superior heat-tolerance and are commonly grown in places with relatively warm weather such as the south of France.

'Nevada' has thick, bright, lime-green leaves that form heavy, upright heads like a loose romaine. Plants have good disease resistance and grow well in all climates.

'Rouge Grenoblois' is a bicolored Batavian in green and crimson.

Mâche or corn salad (Valerianella locusta) is also called lamb's lettuce. Mache is from the Valerianaceae family, which includes the garden perennials Jupiter's beard and valerian. Mache's glossy, spoon-shaped leaves are mild with a sweet nutty flavor and grow in attractive small rosettes.

'Vit' is a popular variety that can be grown in both spring and fall, and produces a dense mound of firm, leaves with tender flavor. With good cold tolerance, it is also ideal for overwintering when grown in milder climates.

Large-Seeded Mache is best grown in spring because it can handle higher temperatures before bolting. Mache reaches full size in about seven weeks.

Garden Sorrel (Rumex acetosa), sometimes called spinach dock, is a member of the buckwheat family, Polygonaceae. It is a hardy perennial in USDA zones 4 to 9, but often grown as an annual.

As a perennial, it is one of the earliest greens to harvest in the spring. It continues to produce into fall and often early winter, withstanding temperatures well below freezing. The long green spoon-shaped leaves have a sharp, mildly sour, lemony flavor.

'Red Veined Sorrel' has contrasting dark red stems and veins for added color. Harvest of small leaves can begin at any time, while leaves are fully mature in 55 to 60 days.

This is the third of a four-part series from the National Garden Bureau about greens. The previous articles can be read here and here. The last one -- how to grow greens -- will be posted tomorrow.