by George Buehler

The pomegranate originated in the Mediterranean region, in the Himalayas, and in Southern China, and has been cultivated for centuries. It is widely grown in subtropical climates (Zones 8 to 10 in the US). The name comes from malam punicum (apple of Carthage). Pomegranate is derived from pomum (apple) and granate from granatum (meaning many seeds).

It has glossy, bright green leaves carried on reddish stalks which create an interesting display during the growing season. The pomegranate has flowers which range in color from white to yellow to orange-red. Looking at the Japanese bonsai photos, you probably noticed the beautiful pomegranate trees, with dramatic gnarled shapes and twisting bark. Pomegranates have some wonderful properties for bonsai. First, they have bark that will quickly look very old. Second, they form flowers and fruit more easily than most other bonsai. The fruit will last many months with proper care. If you are interested in a showy flowering tree, try the pomegranate. Do not expect to get an 8" trunk, even on aged bonsai pomegranate, trunk development is extremely slow. However, few bonsai nurseries carry them. When they are found, they are mostly young trees. You will have to hunt for a good tree. However, the results will please you when you see the tree covered with blooms in the spring and sometimes throughout the summer

SOIL
The pomegranate adapts to a wide range of soil types but, according to the literature, prefers a 50/50 mixture of grit and organics. I personally use a 2/3 grit 1/3 organic mix, and it seems to thrive. I have found that it does like a slightly acidic media. Although it likes water, it must have excellent drainage.

WATER
Pomegranates like plenty of water during the growing period, especially when the buds are swelling and when the fruit is growing. During the dormant period, they should be kept just moist. As stated above, they also like a slightly acidic media and therefore should be treated periodically with an acidic fertilizer such as MirAcid.

WINTER STORAGE
Most of the bonsai literature lists the pomegranate as a subtropical. Most references list a survival temperature down to 35 degrees F. I leave my pomegranate outside until the leaves start falling, being cautious not to allow it to be hit by frost. This sometimes means moving the tree in and out a number of times. When all the leaves (or at least most of them) have fallen, it is moved into an unheated garage. The tree is left in this storage situation until around the first of January. It is then moved to the basement grow lights where the temperature is about 60-65 degrees F. Within about 2 weeks, the tree will start leafing out. The leaves are about ½ size of summer growth and are a bright green. When the tree was stored under grow lights, the leaves were light green and normal size. This year, the tree started flowering in early February. All the flower buds were cut off to lessen the sapping of energy. After flower bud removal, the tree was fertilized with a ½ solution of fertilizer.

REPOTTING
Repot in late winter or early spring before the buds leaf out. In younger plants, yearly repotting is required; but as the plant ages, repotting should be every other year. For older trees, repotting can be every third year. Root pruning should be done with care because there is a direct relationship between the main roots and its branches. As the artist develops a fibrous root system, the removal of the root mass should be done gradually to prevent the loss of branches.

SUN EXPOSURE
Full sun is preferred by this species. However during very hot dry periods, placement where the pot receives some shade during the hottest part of the day is ideal. When the tree is in full sun, copious watering is required.

FLOWERING
Flowers range in color from white to orange-red and are self pollinating. Most of the pomegranate bonsai have the orange-red flowers since the nana is the predominant variety. They typically bloom in mid summer, continuing into fall. However, if the tree goes through a completely dormant period (see wintering), blooming may start as early as late February or early March. If the pollinated flowers are allowed to fruit, only three or four fruit should be allowed to grow. Allowing too many fruits to remain on the tree will sap the energy of the tree.

PRUNING/WIRING
Hard pruning is best done in late winter or early spring. Trim new shoots that have 4 to 6 leaf pairs to one or two pairs throughout spring and summer as needed. Pinching out the new growth is generally preferred over scissoring. Pinching/trimming should be stopped from June through August to allow the tree to set its flower buds for next year. Be careful to avoid pinching the short rounded shoots that are the flowering shoots. After flowering, the tree can be hard pruned again to maintain the style. All styles are seen except formal upright and broom. One of the drawbacks of the pomegranate is that new growth is straight and uninteresting, and wiring is almost mandatory. Wiring can be done at any time except when the plant is flowering. Wiring is best accomplished on young shoots which are pliable and easily bendable. Raffia is normally used to protect these tender shoots. Older branches are very brittle and can easily crack on bending. To bend the older woody branches, the branch should be massaged to loosen the cambium prior to wrapping the wire and subsequent bending. Even then, caution should be exercised!

PROPAGATION
Propagation is accomplished by mid summer soft wood cuttings, leaf-less hardwood cuttings in winter or air layering. Bottom heat and rooting hormone is required for cuttings.

PESTS
The tree is prone to scale and spider mites. Normal insecticides or a soap spray and wash are used as treatment. Good air circulation helps alleviate these problems.

FERTILIZATION
As with most flowering trees, the pomegranate needs high phosphorus fertilizer and applications of iron several times during the growing season to prevent chlorosis. Begin fertilizing when buds swell and stop during the flowering period. A balanced fertilizer should be applied every other week in spring and summer, alternating with a high phosphorus fertilizer. Periodic treatment with MirAcid will keep the soil slightly acidic which the pomegranate likes.