Amid questions about citrus, peaches and apricots, occasionally I get asked about a lesser known, but equally useful fruit: the Chinese date or jujube.
Ziziphus jujuba is the scientific name of this wonderful tree, but most people simply call it by its common name, the jujube. A member of the buckthorn family, it brings an interesting shape, deep green leaves and tasty fruit to a landscape. It is widely grown in hot, dry climates around the world.
The jujube makes an excellent landscape plant. It provides shade and has a canopy of leaves thick enough to make a good screen. It produces lush fruit that can be eaten fresh, dried like a date or candied. If you are into wood carving, you will just love the opportunities the wood provides. The wood from the jujube is reddish, close-grained, fine-textured, hard, tough, durable and polishes well. The wood can also be used to make furniture and other useful items. For the less artistically inclined, it makes great charcoal.
The jujube tree mixes well with lawns, shrubs and bedding plants but it strikes an especially attractive silhouette when planted all by itself. Over time it develops a graceful, gnarled shape that gives it character and individuality.
The tree grows at a slow to moderate rate until it reaches a mature size of fifteen to twenty feet tall and about ten to fifteen feet wide. These dimensions make this tree a little smaller than other trees commonly available for planting in local landscapes. Thus, the jujube is an ideal candidate for planting in smaller yards.
The tree is best identified from the structure of the leaves. Each glossy, bright green leaf has three prominent veins that run lengthwise along the leaf. Most leaves are about one to two inches long. In the fall, these same leaves turn a bright yellow color in anticipation of the winter season.
The flowers of the jujube appear in late spring and early summer. The many clusters of small, yellowish flowers produce the fruit that will ripen in the fall. The fruit is harvested for eating fresh off the tree when it begins to turn from yellow-green to reddish brown. The fruit will have a crisp texture and taste like a sweet apple. Once the fruit reaches the stage where it is completely brown and mushy, it is better for drying.
The fruit from seedling trees are generally smaller than the regular fruiting varieties. What are seedling trees, you ask? Seedling trees are trees that are still on their own roots. It is quite common in horticulture circles to graft fruit varieties, like peaches, apples and citrus, onto the trunk and roots of a different variety. This management step usually yields larger fruit and a more vigorous tree.
In the jujube, seedling fruit are usually about one-half to one inch long. Fruiting varieties that are grafted usually produce fruit from one and one-half inch to two inches long. So, if you choose to plant a jujube from seed, just remember that you may get smaller fruit. The two most common cultivated varieties are ‘Lang’ with one and one-half to two-inch, oblong fruit and ‘Li” which produces two-inch, round fruit. Both varieties produce better if both are planted next to each other for cross pollination, but ‘Li” will produce some fruit if planted alone.
The jujube tree has roots that penetrate deep into the soil. Because of this, it can access water that is normally unavailable to other, more shallow-rooted plants. When we irrigate the jujube tree, it is best to let the water run slowly over the ground so that it can fill the entire root zone. The tree will, however, tolerate drought and the hot, dry environment of the desert. It grows better in well-drained, fertile soils than it does in shallow, hard soils, but it does just fine in our salty, alkaline soils.
Unlike many of our frost sensitive fruit trees, like citrus, the jujube is rarely bothered by the cold weather found here in our warm deserts. Because the plant loses its leaves during the winter and flowers relatively late in the spring, frost doesn’t bother it. However, in higher elevations, the tree will not produce much fruit where the summer growing season is short.
The jujube tree needs only a minimal amount of fertilizer each year to be happy. I would give it no more than one pound of actual nitrogen each year. If you use ammonium sulfate, 21-0-0, the year’s total would come out to only five pounds of fertilizer for the entire year. This total should not be applied in anything less than three applications during the year. A good approach would be to apply one-third of the fertilizer in each of the months of February, May and August. Sprinkle the fertilizer onto the surface of the soil and then let the irrigation water slowly trickle onto the surface of the soil until it wets the entire area beneath the canopy of the tree. The water will move the nitrogen into the soil profile.
One drawback of the jujube is its tendency to produce sucker growth from the roots. These individual sprouts of little trees will eventually play havoc with lawn mover blades when they begin to be thick enough to cause problems. The tree is also quite susceptible to cotton root rot, otherwise known sometimes as Texas root rot. The sucker growth can be kept trimmed, of course, but there really is nothing to be done if root rot organisms are present in the soil. Root rot kills quickly and silently.
It is not necessary to do a lot of pruning to maintain the tree. The best time to prune is in winter during the months of late December, January and early February while the tree is dormant, that is, when the leaves are off the tree. Other than the need to cut out the occasional rubbing branch, to slightly shape the tree, to encourage the weeping habit or to reduce size, very little pruning is actually needed.
If you haven’t guessed by now, I really think the jujube is a good fit for desert landscapes. Yes it has a few spines, but the shade, desert hardiness and fruit make up for that and the other few problems inherent to the jujube.
If you have questions, you can reach one of the Master Gardeners at the Cooperative Extension office, 820 E. Cottonwood Lane, Building C, in Casa Grande. The telephone is (520) 836-5221, extension 204. The author’s email address is gibsonrd@ag.arizona.edu.
The University of Arizona is an equal opportunity, affirmative action institution. The University does not discriminate on the basis of race, color, religion, sex, national origin, age, disability, veteran status, or sexual orientation in its programs and activities.
Rick Gibson
Extension Agent, Agriculture
University of Arizona Cooperative Extension
820 E. Cottonwood Lane, Building C
Casa Grande, Arizona 85122
Voice: (520) 836-5221
Fax: (520) 836-1750
email: gibsonrd@ag.arizona.edu
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