Even without bearing fruit, these fast-growing, evergreen trees are ornamentally attractive with their glossy leaves and tubular red flowers. But, of course, it’s the fruit that these trees are known for. The red, thick, leathery, inedible rind protects an abundance of sweet, juicy seeds that are packed with beneficial nutrients. Outdoors, pomegranate trees typically grow to reach around 12 to 16 feet, although they can sometimes grow as tall as 30 feet. However, dwarf varieties are available, and their compact form (sometimes just 2 feet tall) means they’re often a better choice for growing indoors. Just be aware that the fruit from a dwarf pomegranate tree isn’t nearly as sweet.
How To Grow Pomegranates Indoors
Growing pomegranates indoors is a good option if you can’t offer them the warm and sunny outdoor conditions they need to thrive.
Sunlight
If you want your pomegranate tree to produce fruit, it will need between 6 to 10 hours of sunlight per day. Ideally, you’ll want to select a south or west-facing window. They can tolerate partial shade, but you shouldn’t expect a fruit harvest.
Temperature and Humidity
Outdoors, pomegranate trees do best with hot, dry summers and cool winters. For an ideal growing season, temperatures should be above 80 degrees Fahrenheit. Pomegranate trees like warm temperatures but not high humidity. Flowering is a problem if there is too much humidity in the air. If you’re experiencing high levels of humidity, you might need to use a dehumidifier. Also, avoid rooms that get fogged up like the bathroom or keep your plant near a fan or open window. In the winter, they are more cold hardy than many other fruit trees (with many cultivars coping with temperatures as low as 10 degrees Fahrenheit), so you don’t have to worry if your home isn’t always heated. If your home does stay warm throughout the year, you might notice the pretty flowers bloom even in the colder months.
Watering
Although this is a drought-tolerant tree, it needs a thoughtful watering schedule if you want to see healthy fruit production. This is especially important in the first few years, while the tree is establishing. Keep the potting mixture moist but not soggy—too much or too little water can prevent fruit production. Waterlogging can also lead to fruit that splits readily, and this can attract pests and problems with fungal disease. Be vigilant during those early years because container-grown plants dry out more quickly than those grown in the ground. You might need to water as much as every day when temperatures are warm—you’re looking for the soil to be slightly dry when you water it again rather than completed dried out.
Fertilizer
Container-grown pomegranate trees will benefit from a biannual feeding in early winter and early spring for the first two or three years while establishing. Often adding organic, nitrogen-rich compost or mulch can be enough. Be sure not to add too much fertilizer, especially once the tree is well-established. You don’t want an abundance of foliage rather than fruit.
Pruning and Maintenance
Don’t opt to grow a pomegranate tree indoors unless you’re ready to do a fair amount of pruning in the first few years. Without it, it will have a wide, bushy, spreading shrub-like appearance. Regular pruning also encourages the healthy development of new shoots, and you’re more likely to get a good fruit harvest. Young trees produce a lot of shoots from their base, and you only want to allow a few of those to grow. You should prune the rest back, along with any suckers that form. Cut dead branches back in the spring. As the fruits begin to grow on the branches, thinning them out allows healthy fruits to grow to their optimal size, and you’re less likely to experience branch breakages.
Pollination
If your pomegranate tree is kept indoors year-round, it won’t be visited by the pollinators that find it attractive. So, if you want to try for a fruit harvest, you’ll need to pollinate the flowers by hand. When the tubular flowers open and you can see the stamens, use a small paintbrush, soft-bristle toothbrush or cotton swab to transfer the pollen from flower to flower. Be aware that the blooms come in a hermaphroditic and male form. Only the hermaphroditic forms can produce fruits—these have a more rounded, bell-shaped base when compared to the narrower, vase-shaped bases of male flowers.
Container and Size
The size of your container will depend on the pomegranate cultivar you select. For larger trees, a 10 gallon-sized container may be required, but this won’t be necessary for smaller dwarf varieties. A container that is wider than it is deep is a good option because of the shallow, spreading root system. Decent drainage on the base is also a must. Your plant will likely need repotting every few years to prevent it from becoming root-bound.
Potting Soil and Drainage
Pomegranate trees aren’t too fussy about the type of potting soil they grow in, as long as it drains well. This means a light mix with additions of peat, perlite or vermiculite works well. Waterlogging is not this trees friend.