Under a box is where to grow Belgian endive

Sunset, April, 1988

Under a box is where to grow Belgian endive

One of the easiest gourmet greens to grow is Belgian endive, especially if you use the method shown here. Instead of the traditional labor-intensive digging and forcing indoors, Sonia and Gustavo Kuster of La Jolla, California, simply cut back mature plants as shown below, then cover the remaining stems with a light-excluding box. The new leaves that grow under the cover are blanched and perfectly succulent. With this method, gardeners in mildest climates of northern California can sow seeds this month or in fall.

Belgian (or Brussels or French) endive is the same as witloof (or "white leaf"), a strain of the 3- to 6-foot roadside weed chicory (Cichorium intybus)--common throughout the West. Because Belgium is the center of witloof culture, the vegetable is known as Belgian endive. Another strain is grown for its roots, which, when roasted and ground, serve as a substitute or extender for coffee.

The Egyptians, Greeks, and Romans all knew and used chicory leaves. But the cultivation of witloof began around 1850, when it was discovered that blanched plants could be grown in a dark cellar in winter when the soil outside was frozen.

Unlike northern European gardeners, ones in mild climates aren't limited by soil that freezes, so lifting the roots and bringing them indoors is not essential.

Sowing the seeds

Several mail-order seed companies list Belgian endive, usually with other chicories. Seeds germinate best in cool temperatures; if started in spring, they might produce carrot-size roots by fall. Seeds sown in fall will likely produce large roots by the following May or June.

Deep, well-prepared soil that roots can easily expand in is best. Work in well-rotted compost, nitrogen-fortified ground bark, or other organic material to a depth of 12 to 15 inches. Fertilize lightly, if at all; too much nitrogen stimulates leaf growth at the expense of roots.

Sow seeds directly in soil as you would lettuce or carrots, in rows 12 to 18 inches apart. Seedlings are frost hardy. When seedlings reach 4 inches tall, separate and replant them about 6 inches apart.

Growing blanched heads

Remove the greens once root crowns are about 1 inch across. Don't wait too long; if greens begin to bolt, the root will produce many small shoots after cutting instead of one large one. In summer, time from cutting back to harvest is about three weeks; in winter, five to six weeks.

For tightly bunched heads--known as "chicons"--cover the root after cutting back with about 8 inches of mixed peat moss and ground bark. Blanched but without a soil cover, heads are usually loose, as in the picture at upper left.

After harvest, roots will sprout. You can separate sprouts and grow as seedlings.

Photo: Blanched leaves of Belgian endive are ready to harvest. They grew from mature roots

Photo: Cut tops off mature plants five to six months after sowing seed. Green leaves make slightly bitter additions to salads

Photo: Covered with light-excluding black plastic, wood box goes over endive stems. It stays in place until harvest; no extra water is needed