Gardeners who visit my backyard garden-orchard in Thousand Oaks, California, usually ask why I have so many jujube trees. My answer is easy: No other tree gives me so much pleasure for so little effort.
The jujube (pronounced juh-ju-bee or juh-juh-bee) is a member of the buckthorn family, or Rhamnaceae. Its botanical name is Ziziphus jujuba, and its common names is Chinese jujube, or sometimes, just jujube. Though the plant's origin is probably Syria, it was distributed throughout much of the Mediterranean region at least 3,000 years ago and today is most widely grown in China.
This deciduous tree grows 12 to 15 feet tall, although trees are known to reach 30 feet. (The largest known jujube tree in the United States, at the Fort Worth Botanical Gardens, measures over 40 feet high and wide.) Over time trees develop a graceful, gnarled shape. Most varieties have thorns on young branches. Its leaves are 1 to 2 inches long, leathery, and shiny bright green. Tiny yellow-green flowers are about 1/4-inch wide.
Fruits ripen in late summer to early fall. Many people enjoy them fresh, after they turn from green to brown, but before they dry and shrivel. At that stage, their flavor and texture is something like a very sweet apple, but not as juicy. Unlike most fruits, jujube will dry on the tree after ripening. Although dried jujubes are not as sweet as true dates, its sugars do concentrate, and the flavor is very similar. Dried fruits require no preservative, and they last "forever"--I've pressed several growers on this point, and all agree--though humidity in some regions may slow drying and limit the life of dried fruits.
Jujube grows throughout most of the southern half of North America. For best crops, the tree needs a long growing season and hot and dry weather during ripening. About the only parts of the United States where jujube can't grow are in the North (USDA Zones 5 and colder) and the Gulf Coast where summer rain and humidity prevent optimum fruiting.
Trees thrive in most of California, from interior valleys in the north to the Sierra foothills, and throughout the southern region of the state. In Oregon, the region surrounding Medford is well suited. In the southwest deserts, trees grow well from Palmdale in California to Las Vegas and in Arizona from Bisbee to Phoenix. Most of Texas from Houston north to Muskogee, Oklahoma, is jujube country, then east to the Atlantic seaboard and as far north as Trenton, New Jersey.
Although average winter minimum temperatures between -5° F (zone 6) and -15° F (zone 5) are the likely hardiness limits, trees have survived -25° F.
Plant jujube in a location that receives full sun and has well-drained soil with a neutral or slightly alkaline pH. Once established, the roots are very tolerant of salinity, drought, or standing water. During periods of extended drought, the tree will likely survive but without a crop. Also, irrigations after a brief drought may cause fruits to split.
Plant bare-root trees in January or February or whenever plants are available. Amending soil is not necessary. Spread roots over a cone of soil in the center of the planting hole, and adjust the final height until it is equal to or slightly above the original soil grade. Trees often bear some fruit the first year. Bare-root trees cost from $20 to $40.
Trees require very little pruning or training. The best time to prune for repair or shaping is late winter or early spring before the tree breaks dormancy. Fruits are borne on long-lived spurs, much like apples. Root suckers can be a nuisance, but most gardeners consider them a minor one. The jujube is virtually disease-free, and most insects ignore it. In desert regions, you'll probably have to compete with birds for the fruit, and Texas root rot sometimes occurs.
All jujubes are self-fruitful, meaning you only need one to get fruit, and all contain a pointed seed.
'Li' is the one to plant if you have room for only one tree. Fruits are abundant, round, 1-1/2 to 2 inches in diameter, and sweet. It matures early, a great benefit in short-growing-season areas.
'Lang', compared with 'Li', is taller, and the fruit is a bit more elongated or pear-shaped, about 3/4 inch in diameter and 2 inches long, and has thicker skin. The fruit is a bit less sweet than that of 'Li' and best eaten dried. Branches are nearly thornless.
'Sherwood' fruits are smaller than 'Li' and ripen later. They keep well in the refrigerator up to 6 weeks. Discovered in the southern Louisiana woods, the tree has an attractive, narrow, weeping shape.
'Silverhill' (also called 'Tiger Tooth') produces elongated fruits that are excellent for drying.
'So' produces high-quality, round fruit on a zigzag-shaped tree.
'Shui Men' (or 'Sui Men') is a highly regarded midseason variety. Its fruits taste good fresh or dried.
'GA 866' is noted for its remarkably high sugar content.
Trees are available in nurseries in the West and Southwest, both as bare-root in winter or in containers during the summer. You can also order jujube trees from several mail-order nurseries.
To make glazed jujubes, halve and seed the ripe (but not dry) fruit and place in equal parts water and brown sugar (just enough to cover the fruit). Bring to a moderate boil and simmer for 20 minutes, let cool, then boil for another 20 minutes. Drain the fruit, and add rum and/or vanilla to taste. Then place the halves, cut side down, on a cookie sheet in either a food dehydrator or oven at 180oF for about 24 hours. Dry to taste, and store them in the refrigerator in airtight bags.
Edward T. Hager, M.D., is a former director of the California Rare Fruit Growers, Inc., an organization that educates gardeners about rare or exotic fruits.