Punica granatum, the pomegranate tree, is a tree in a class of its own. Producing an unusual fruit filled with little arils or sacs of sweet juice, this tree originated abroad and has become a hit in the United States.
We all know the pomegranate as a fall and winter fruit, visible in the cornucopia at Thanksgiving or scattered amidst pine boughs at Christmas. But the juice of this fruit is used year-round in grenadine for mixed drinks, and is packed with antioxidants and vitamins. They’re an amazing addition to a healthy diet!
It can be grown as a small fruit tree or as an attractive shrub, in small gardens or large. We’re packing this full of tips for growing the happiest pomegranate trees you can!
Good Products For Pomegranate Growers:
- Monterey BT Spray
- Garden Safe Neem Oil Extract
- BirdBlock 604 Reusable Bird Netting
- Monterey Liqui-Cop Fungicide
Quick Care Guide
|Scientific Name||Punica granatum|
|Height & Spread:||16′-20′ tall as tree, often kept under 6′|
|Soil||Fertile loam, well-draining|
|Water:||50-60″ per year (about 1″ per week)|
|Pests & Diseases:||Pomegranate butterfly, mealybugs, scale, thrips, whiteflies, mites. Susceptible to leaf spots, fruit rots, and botrytis.|
All About The Pomegranate Tree
The pomegranate’s origins are from Iran southeast to India, but once it was discovered to be tasty it spread like wildfire. Spoken of in mythology and religious literature, the pomegranate permeated all forms of history throughout Europe, Asia, and Africa. The Egyptians used it in artwork; the Greeks told tales of Persephone eating but a few arils while in the Underworld. It was praised in the Old Testament of the Bible.
Somewhere during the late 1800’s, a cultivar named “Wonderful” made it to California, and it became a popular fruit here. But it’s also been grown throughout the southern United States, in Mexico and South America, and in virtually every other warm climate worldwide.
This multi-stemmed shrub can be grown as a small tree or left in its shrubby state. Like pineapple guava, it will form shoots directly from the root mass, so it needs to be trimmed back at the base if grown as a tree. Its leaves are deciduous in cooler climates and evergreen in warm ones.
If maintained as a shrub form, it often is kept about 6′ tall. As a a fruit tree, it can reach heights of up to 20′ tall, but is often maintained as a dwarf.
Blooming in July and August, the flowers are a vibrant orange-red color. They’re quite beautiful, providing a showy display of color on the tree. Female flowers, if pollinated, will turn to fruit. The base of the flower is a leathery, firm material which will form the bud end of the future fruit, and the petals and stamens will dry and may fall off.
The leaves are long and slender. In warm climates it may be evergreen. However, in most areas they will turn yellow. Starting in fall, the tree will lose its leaves, only for them to return in the spring.
There are a variety of cultivars available. In the United States, some of the most common are Russian Red, Wonderful, Red Silk, and Grenada. A dwarf variety called Nana is popular in Japan for training to bonsai. It produces fruit which is only 2″ across, and can easily be container-grown.
Punica granatum, the pomegranate tree, grows best in zones 8-11. While indoor growing is an option, a pomegranate shrub typically won’t perform well inside. It may have foliage, and might even produce flowers, but rarely will they fruit.
Producing an abundance of flowers and fruit is easy with these shrubs and trees. Follow the care tips below and you’ll find yourself getting fruit within a few years!
Light & Temperature
As with most trees, full sun is the best choice for your pomegranates. While it can tolerate partial afternoon shade, it’ll need at least 8 hours of sunlight per day for best growth.
Pomegranates fruit best in areas which have long, hot summers and cool winters. Areas which are often in the 90’s during the summer are perfect. But by cool winters, I don’t mean serious cold. Temperatures below 12º F will severely injure your plants. People growing their pomegranates as shrubs should use some form of frost blanket if the temperature dips down into the 30’s. Tree growers should also provide frost protection, either as a frost blanket or by wrapping the trunk and branches.
Depending on your variety, your pomegranate may be more hardy in winter climates. Select a type which grows well in your region.
These trees grow best in hardiness zones 8-11. In colder zones, they can be container planted and brought indoors for the winter, but should be returned outside when it warms up. Be sure to provide lots of light for overwintering plants!
Water & Humidity
While pomegranate trees are drought tolerant, they perform better when they have enough to drink. The axils need liquid to become full of juice, and shrub or tree growth suffers in an extended drought.
Depending on your average soil moisture, you may need to water more or less often. A thick layer of mulch can prevent soil moisture evaporation and reduce watering frequency as well.
It’s hard to establish an exact amount to water pomegranates because so much depends on the climate they’re in. A good guess is between 50-60 inches per year, which works out to be about 1″ per week or a bit more. As you won’t need to irrigate as much during the late fall and winter since the tree is dormant, that reduces the need a bit. Rain also counts towards your irrigation needs, so don’t forget to factor that in!
The major times of year to provide added moisture will be during the hottest parts of late spring, summer, and the earlier warm months of fall. At these points, rain frequency is often less. But don’t panic if it goes a bit dry before you provide more moisture. Your pomegranate shrubs will survive.
While these trees will tolerate humidity, they prefer a more arid environment.
Fertile loam is ideal for your pomegranate shrub or tree. It must be well-draining, but rich in organic matter. Add compost before planting if you need to boost the organic content.
Don’t give up hope, though. Your plants will still grow even if your soil isn’t perfect. Pomegranates can grow in a wide range of soil types. From acidic and loamy to alkaline and calcareous, they’ll still hold on. They’ll even do alright in gravelly, rocky soils.
Avoid hard packed clay at all costs. That soil type is the only one which they will not thrive in. The clay can impede drainage, and if water pools up around the tree, it can create major problems.
The pH range of your soil should be neutral to slightly acidic. While your trees can grow in alkaline soil, they often have problems absorbing iron and other micronutrients.
Nitrogen is the most important nutrient for foliage. For the first few years, it’s essential to make sure the trees get extra nitrogen. Since the flowers eventually become fruit, it’s definitely important as well to fertilize for flowering and fruiting in subsequent years.
Skip fertilizing the first year, as your soil should be rich enough to support the plant. In the second year, you should apply 1-2 cups of a high-nitrogen fertilizer over the course of the year. Apply in early spring and again in early fall. Your pomegranate shrub will appreciate it, and it will help get it more established.
In subsequent years, opt for a balanced formula that’s at least 10-10-10 NPK. You can use a fertilizer which is optimized for fruiting shrubs and trees as well. Again, fertilize in early spring and early fall. Do not fertilize in the late fall or winter as the tree will go dormant. Your tree shouldn’t require fertilizer during the peak of summer.
When fertilizing, spread your granular fertilizer from 6″ away from the trunk to about 6″ outside the tree’s canopy. Work it loosely into the top of the soil and then wet the soil to keep it in place.
Pomegranate propagation is done in one of two methods. Either it can be germinated from seeds, or one can take semi-hardwood or hardwood cuttings.
Cuttings should be about the diameter of a pencil and 6-8″ in length or a smidge longer. There should be a leaf node on the cutting an inch from the base. These cuttings should not have leaves on them.
Remove just the surface layer of bark on two sides of the cutting below the leaf node. Be careful not to remove any of the wood, just the bark. Dip the cutting in rooting hormone to just above the leaf node, and place in a well-draining rooting medium. Keep humidity up around the cutting, but ensure neither the soil nor cutting are completely saturated.
Seeds can be extracted by breaking the arils, releasing the juice around the seed. Rinse the seeds off and dry them to remove any remaining aril skin. Once dry, store in the refrigerator for at least a few weeks before sowing, as the seeds need an artificial “winter” before they can germinate. Soil temperatures of 75 to 85°F are required for germination.
Encouraging a pomegranate to fruit can be as easy as waiting for the bees to come… but it isn’t always that simple.
First, you have to be sure your tree is a fruiting variety. There are flowering pomegranate species which bear nothing but flowers, and will never set fruit. The best way to ensure your shrubs are fruiting species is to purchase them from a reliable company.
Most pollination is performed by bees as they’ll get deep inside each flower. If you aren’t seeing lots of bees or other pollinating insects when your shrub is in flower, you may want to hand-pollinate to ensure good fruit production. You can encourage more pollinators to help by planting other plants which draw in pollinating insects.
Hand pollination should be done in the morning. You can use a variety of tools to do this, but I like either soft artist’s paintbrushes or cotton swabs. Once the flowers open in the morning, look for ones which have pollen available to collect. Use the swab or brush to gather pollen, then dust it all over the inside of the flower below the stamens. Move on to the next flower with a bit of the pollen from the prior one and repeat this again.
Underneath the stamens, the flower has a central bump called a stigma. You need to coat the stigma with pollen, especially around the center. Pollen will enter the tiny hole in the stigma’s center and work its way into the flower’s ovary, which eventually becomes the fruit.
Once fruit has started to form, make sure you’re irrigating regularly. To form that delicious pomegranate juice inside the arils, the tree will need moisture — and if you aren’t giving it enough, you can suffer premature fruit drop! Keep your fruit trees watered consistently while they’re producing fruit.
Pomegranate flowers form on new growth at the tips of branches, rather than older wood. Because of that, it’s important to limit any serious pruning to the dormant season during winter. This new growth will form on 2-3 year old branches, so you also want to be very selective.
Skip all pruning for the first year after planting your pomegranate shrub or tree. This gives your young plants time to become established and stretch out their roots.
When growing pomegranate shrubs, you’ll want 3-6 trunks to become established. If your young shrub has fewer than that, allow it to develop more base shoots. You want to select ones which are evenly spaced around the plant. Once you have three to six trunks which you like, you can remove additional sucker shoots as they appear. In the winter when it’s dormant, prune only to shape it. Taking off too much can reduce fruiting the following year.
To grow pomegranate as a tree, wait to prune until the plant is between 2-4 years old and at least 3-4 feet tall. Select 1-3 trunks and remove any other sucker shoots at the ground when they appear.
In both cases, the more light and air the flowers receive, the better the pomegranate fruit set and production will be. Try to open up the middle, removing any secondary limbs that overlap.
There are a few pomegranate problems you might encounter. Let me provide all the tips you need to deal with them!
Your indoor pomegranate may or may not perform as well as other indoor plants. They are known for having a difficult time flowering or fruiting indoors. It’s recommended whenever possible to grow these outside.
In addition, even outdoor pomegranates should be allowed to ripen fully on the tree. Unlike other fruits, they don’t ripen once harvested. To check for ripeness, tap on the pomegranate and listen for a slightly metallic sound. Also, inspect the exterior and make sure it has a beautiful blush of red color. If these signs appear, use sterile shears to clip it from the tree.
Yellowing leaves can be a symptom of many issues. Over or under watering, over or under fertilizing, micronutrient deficiencies such as iron or zinc, and transplant shock are the most common issues. It’s hard to diagnose these problems, but you can do so via trial and error if you start to observe yellowing.
A number of pests can impact your pomegranate shrub. The worst of these are those which target the produce.
Virachola isocrates, also called the pomegranate butterfly, will lay its eggs on flowers or developing produce. Once the eggs hatched, the caterpillar-like larvae known as the pomegranate fruit borer will bore into fruits and wreak havoc. Other forms of caterpillar or stem borers may also be evident. Use bacillus thurigiensis to deal with them.
Birds are also potential pests. They instinctively know that the gem-like arils inside the fruit are delicious. You may need to protect ripening produce with bird netting to ensure you have pomegranates to harvest!
Most diseases that impact pomegranate shrubs are common.
Alternaria materializes both as leaf spots or as fruit rot. Another form of rot, aspergillis fruit rot, can also become an issue. Both of these often appear after periods of rain. While it’s difficult to identify impacted produce, it often has an off-color peel. Keeping the tree free of fungal infections is the best defense.
The other most common disease of pomegranate is botrytis cinerea. This will infect produce during the blossom phase, and can cause blotching and spoilage. Keeping your tree free of botrytis is important too!
All of these fungi can be treated with a liquid copper fungicide. This will also treat anthracnose, another leaf spot disease that can sometimes affect pomegranate foliage.
Finally, botryosphaeria stem cankers and dieback can occur. Common among growers in the southeastern US, these cause brown splotches on stems which can develop into large cankers. It’s caused by two specific fungal pathogens, Neofusicoccum parvum and Lasiodiplodia theobromae. Pruning off damaged branches and sterilizing your pruning shears between cuts is your best option for control. Select pomegranate varieties which are resistant to fungal diseases.
Frequently Asked Questions
Q: How long does it take for a pomegranate tree to bear fruit?
A: Pomegranates ripen 5-7 months after flowering. However, the plant needs to be mature enough to produce. Shrubs and trees usually take at least 2-3 years to come to maturity.
Q: Where do pomegranate trees grow best?
A: California’s the primary pomegranate-producing state in the US, although most southern states are able to grow them well. Areas in zones 8-11 are ideal for pomegranate production.
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