Punica granatum, or the pomegranate tree, can be a lovely addition to your collection. This tree is best known for its bright red fruit, which is quite distinctive; the seeds (technically an aril) burst with a juice that has a strong and unique taste and is filled with antioxidants that may produce significant health benefits. The flowers are also stunning and last for months.
The pomegranate tree is fairly small – its dwarf varieties grow as low as two feet high – and can flourish in pots, making it a good option for container gardeners. Though the tree is not particularly difficult to cultivate in a container, it does require regular care in its early years: if you choose to grow it from infancy, be prepared to prune and trim it fairly often.
The Dwarf Varieties
These are small enough to be considered large shrubs and are best suited for container gardening. However, some of these varieties are ornamental, so make sure you buy a variety that will produce fruit: for instance, the ‘Wonderful’ variety, which is extremely popular and available in many garden stores. Their fruits have a thick outer rind and are filled with juicy arils.
Pomegranate trees need lots of sunshine every day to thrive, so make sure your tree’s container is in full sun. If necessary (though it isn’t ideal), they can tolerate partial shade.
Once fully mature, pomegranates are fairly drought tolerant. Newly planted trees need lots of water to develop. Depending on the size of your pot, the denseness of your soil, heat, and wind, your pomegranate may need to be watered frequently--even daily or even twice a day during the heat of summer. While they don't want to sit in water, try to keep the soil damp, not wet.
Though these trees tolerate a wide variety of potting soil types, one constant is that their soil must be well-drained; keeping the pomegranate tree in waterlogged soil will surely damage it. A soil with lots of organic matter is best. Make sure the pot you choose has good drainage in the bottom. It is also a good idea to elevate your container with pot feet.
Like most trees growing in containers, pomegranate trees will need regular fertilizing. Mix a slow-release organic fertilizer into the soil when you pot it up and then use a diluted liquid, organic fertilizer every few weeks during the growing season.
Taking care of your tree through regular pruning is extraordinarily important, especially in the first two to three years. Young pomegranate trees produce lots of shoots from the base: only allow a few of them to grow in the shape you want and prune the rest back. There will also be suckers that need to be pruned, and you should get rid of dead branches in the spring.
Once you’ve shaped your tree into your desired form over the first two or three years of its life it won’t need to be pruned as much, though periodically removing dead material from the tree is still a good idea.
Pomegranate trees will first start to regularly produce fruit around their fifth year. When they do, let the fruits mature to a deep red before you remove them – if the skin cracks, you’ve waited too long. For best results, snip the pomegranates off the tree with cutters rather than handpicking them.
In general, this is an easy tree to grow in a container, especially once it’s fully mature and no longer requires much care. They don’t have any major pest or disease problems, although they are susceptible to blight – keep an eye on the leaves for discoloration. Remember also that pomegranate trees, even the tiny varieties like ‘Nana’, may require re-potting if they become rootbound or the roots have begun to protrude from the bottom of the container or the plant is looking cramped.