Hardy Pomegranate Pollination - Ask Extension
Good afternoon,
I read this article (https://marylandgrows.umd.edu/2023/01/20/fruit-in-your-future-start-with-small-fruits-not-tree-fruits/), and ...
Knowledgebase
Hardy Pomegranate Pollination #892294
Asked February 04, 2025, 3:37 PM EST
Good afternoon,
I read this article (https://marylandgrows.umd.edu/2023/01/20/fruit-in-your-future-start-with-small-fruits-not-tree-fruits/), and I'm interested in planting a couple of hardy pomegranates in my yard, I understand these plants are self-pollinating, but I have also read that having multiple plants can increase fruit production. I would like to know if I can achieve this using two plants from the same cultivar, or if these need to be from different cultivars. If the case is the latter, are you able to recommend two cultivars of hardy pomegranate that I can use?
Additionally, can you confirm that I should not expect much deer pressure for these pomegranates?
Baltimore County Maryland
Expert Response
A cultivar has specific genetics that make it unique, and all plants of the same cultivar are (in theory) genetically identical to each other (that is, clones), because those features are what gives a cultivar its particular traits that need to stay consistent. Therefore, they cannot cross-pollinate because the pollen in one plant's flowers is the same as that in the other plant's flowers. (For plants capable of self-pollination, moving pollen between two plants of the same cultivar would be no different than a flower being fertilized by its own pollen, so the second plant becomes unnecessary unless someone just want a bigger harvest overall.) Different cultivars have different genes, so are compatible for cross-pollination (as long as other factors align, such as bloom time, which is not an issue for pomegranates like it can be for, say, apple trees).
We don't have a reference list of pomegranate cultivars, though online suppliers such as Edible Landscaping probably does. Even though our blog article is written for a general Maryland audience, hardy pomegranate is generally suitable only for Maryland's warmer southern and shore counties (even there, they don't always survive unscathed), though you can always experiment to see how they fare. Look for cultivars with noted origins in central Asia, as these supposedly tend to be the most cold-hardy.
Part of the issue is winter hardiness overall, where a cold snap could kill branches, but the main issue is length of the growing season. Pomegranate blooms so late in the growing season compared to common fruits that we cut it pretty close when it comes to having enough time for ripening. (They take an average of six months after pollination, or about 180 frost-free days. Maryland ranges from 150 to 225 frost-free days, depending on location and some variation in frost dates from year to year.) Some cultivars ripen slightly faster than others, so those would be more suited to cultivation in our area so they can hopefully be harvested just before we start to freeze. Fruits do not ripen once picked, so they cannot be rescued before frost and ripened on the counter.
You can try using microclimate to your advantage, though, by placing plants near sources of reflected and retained heat, such as by a wall, stone pile, or pavement (as long as the rest of the root system has enough good soil). Fortunately, pomegranate fruits are reportedly at their best when developing in periods of high heat, and the warmth radiating from such surfaces might boost its winter survival odds as well. (All you may need is a few degrees to make a difference.)
While other insufficiently-hardy fruits can be overwintered indoors, like citrus, pomegranate reportedly does not do well when brought inside as a houseplant. If you wanted to experiment, a cool greenhouse would better meet their needs than under grow lights (or, worse, with no supplemental light) indoors. If you’re not concerned with active growth or leaf retention, perhaps a potted specimen could spend the winter in a sheltered, unheated garage to take the edge off the worst of the cold. You could also see if wrapping an in-ground plant for the winter, as gardeners do with figs, is successful. Roots growing in the ground are going to be more insulated than those in a container for the winter, but that risk is alleviated a bit when the pot can be moved into a sheltered area, like a cool garage. Keep in mind that potting these shrubs would restrict their growth a bit, though, as the roots have limited space compared to growing in the ground. It's a trade-off between winter risk in the ground and potentially stunting plants somewhat by keeping them in pots that are easier to protect for the winter.
We have little experience with deer pressures on pomegranate, since the fruit is so rarely grown in Maryland. Non-Extension sources online suggest it is not something they usually eat, but we aren't certain how reliable that information is. Fencing a young plant would be prudent, since damage is more substantial at that age from curious deer sampling foliage or branches.
Miri
We don't have a reference list of pomegranate cultivars, though online suppliers such as Edible Landscaping probably does. Even though our blog article is written for a general Maryland audience, hardy pomegranate is generally suitable only for Maryland's warmer southern and shore counties (even there, they don't always survive unscathed), though you can always experiment to see how they fare. Look for cultivars with noted origins in central Asia, as these supposedly tend to be the most cold-hardy.
Part of the issue is winter hardiness overall, where a cold snap could kill branches, but the main issue is length of the growing season. Pomegranate blooms so late in the growing season compared to common fruits that we cut it pretty close when it comes to having enough time for ripening. (They take an average of six months after pollination, or about 180 frost-free days. Maryland ranges from 150 to 225 frost-free days, depending on location and some variation in frost dates from year to year.) Some cultivars ripen slightly faster than others, so those would be more suited to cultivation in our area so they can hopefully be harvested just before we start to freeze. Fruits do not ripen once picked, so they cannot be rescued before frost and ripened on the counter.
You can try using microclimate to your advantage, though, by placing plants near sources of reflected and retained heat, such as by a wall, stone pile, or pavement (as long as the rest of the root system has enough good soil). Fortunately, pomegranate fruits are reportedly at their best when developing in periods of high heat, and the warmth radiating from such surfaces might boost its winter survival odds as well. (All you may need is a few degrees to make a difference.)
While other insufficiently-hardy fruits can be overwintered indoors, like citrus, pomegranate reportedly does not do well when brought inside as a houseplant. If you wanted to experiment, a cool greenhouse would better meet their needs than under grow lights (or, worse, with no supplemental light) indoors. If you’re not concerned with active growth or leaf retention, perhaps a potted specimen could spend the winter in a sheltered, unheated garage to take the edge off the worst of the cold. You could also see if wrapping an in-ground plant for the winter, as gardeners do with figs, is successful. Roots growing in the ground are going to be more insulated than those in a container for the winter, but that risk is alleviated a bit when the pot can be moved into a sheltered area, like a cool garage. Keep in mind that potting these shrubs would restrict their growth a bit, though, as the roots have limited space compared to growing in the ground. It's a trade-off between winter risk in the ground and potentially stunting plants somewhat by keeping them in pots that are easier to protect for the winter.
We have little experience with deer pressures on pomegranate, since the fruit is so rarely grown in Maryland. Non-Extension sources online suggest it is not something they usually eat, but we aren't certain how reliable that information is. Fencing a young plant would be prudent, since damage is more substantial at that age from curious deer sampling foliage or branches.
Miri
