Caren White is a Master Gardener and instructor at Home Gardeners School. She has been associated with Rutgers Gardens for over a decade.
Looking for a way to jazz up your landscape during the winter? Look no further than the winterberry bush with its dazzling red berries.
What is Winterberry?
Winterberry (Ilex verticillata) is a shrub that is related to holly. It is native to the Northeastern US where it grows in marshy areas. If you have a wet area in your yard, this would be a great shrub to plant in that space. But it will also grow just fine in regular soil. Like its holly cousins, it is dioecious with male and female plants. Unlike its holly cousins, it is deciduous, losing its leaves in the fall. Once the leaves have fallen, the bright red berries are revealed. If they are not eaten by wildlife, they will stay on the branches for most of the winter providing color to your yard during a season with little color.
Winterberry is known by many different names such as Black Alder, Brook Alder, False Alder, Canada Holly and Fever Bush. It earned that last name thanks to the Native Americans who used the berries for medicinal purposes. They also used the bark to treat cuts and bruises. Before you try the berries, it should be noted that they are poisonous.
How to Grow Winterberry
Winterberry is very easy to grow. It is hardy in zones 3 through 9. The shrubs range in height from 5 to 15 feet depending on the cultivar. They will grow in partial shade but produce more berries when grown in full sun. They will grow in wet areas as well as normal soil. The shrubs are deciduous, shedding their leaves in the fall. The leaves are dark green turning to yellow in the fall.
To produce the colorful berries, you will need a male and a female plant. They should be labelled at the nursery. If not, you can tell them apart when they bloom in the summer. The male shrub will have small flowers in clusters while the female shrub’s flowers will be more conspicuous and fewer in number. You don’t need to purchase your plants in pairs. One male is enough to pollinate six to ten females. Just make sure that the male is within 40 feet of the females.
How to Grow Winterberry From Seed
Winterberry bushes are as easy to propagate as they are to grow. They can be grown from seed. The seed needs moist, cold stratification. The easiest way to do that is to plant the seeds 1/8 inch deep in a container with pre-moistened soil. Then cover the container with plastic. Place the covered seeded container in your refrigerator for four weeks. The cold in the refrigerator mimics the cold weather that the seeds would experience outdoors. They need this period of cold to break dormancy. The plastic cover keeps in the moisture, preventing the soil from drying out. This mimics the seeds natural environment which is marshy and wet. You should check the soil periodically to make sure that it is not drying out. Germination should occur in 4 - 6 weeks. Plants grown from seed will begin to produce flowers after three years.
How to Grow Winterberry From Cuttings
You can also propagate winterberry from softwood cuttings. Softwood cuttings are cuttings made in the spring or early summer when the plants are actively growing. The cuttings should be made from the soft, growing tips of the branches before they have hardened into stiff, woody branches which happens later in the season. The advantage of using the soft growing tips is that they develop roots very easily.
Make a cutting that is 6 - 8 inches long. Remove the leaves from the bottom half of the cutting. Dip the cut end into rooting hormone then gently press it into moist soil in a container. Place the container on a sunny windowsill. Cuttings take from 30 to 90 days to start growing roots. You will know that your cutting has roots when new leaves appear. Plants with no roots cannot grow new leaves.
Plants grown from cuttings should produce flowers the following year.
Growing Winterberry in a Wildlife Friendly Yard
Winterberry shrubs are perfect for a wildlife friendly yard. The berries are an important food source during the winter when food is scarce. Although they are poisonous to humans, dogs, cats and horses, birds and other small mammals love them. Naturalists have counted 49 different species of birds that eat the berries. That includes not just the usual songbirds but also waterfowl and gamebirds. The term “small mammals” includes mice as well as larger animals like raccoons. But it’s not just the berries that will attract wildlife. Moose, white tail deer, cotton tail rabbits and snowshoe hares will eat the stems and bark if no other food source is available.
Growing native plants is always preferable to the exotics commonly found in most yards. Natives are adapted to our growing conditions and provide a valuable source of food and shelter for the wildlife in our yards.
Winterberry is a native plant that will add a splash of color to your winter landscape as well as provide a welcome buffet for wildlife.
Questions & Answers
Question: Can I purchase female and male winterberry seeds?
Answer: Winterberry is almost always sold as a plant. Very few reputable seed sellers sell winterberry seeds. If you see winterberry seeds for sale, check out the seller very carefully. Make sure that they are a trusted source for seeds before you purchase from them. Most gardeners who want to propagate these shrubs from seed either gather the seed from their own shrubs or get permission from another gardener who is growing winterberry to harvest seeds from those shrubs.
Question: I'm from central Maine. I plan to grow from cuttings. Our veggies are planted until Memorial Day. It's been a mild winter. I located bushes to cut but I'm unsure if they're male or female. Do I need to wait for flowers to ID or would you suggest trimming and labeling to the source to get a head start then use the ones I want and plant the rest elsewhere? Also, when can I plant them on their own?
Answer: An easy way to tell if a winterberry shrub is male or female during the winter is to look for berries. Only the female shrubs have berries. Wait to take your cuttings until after your last frost and the shrubs are actively growing. Right now, they are dormant and won't root. Once you see that the shrubs from which you want to take cuttings have leaves and new shoots, you can take your cuttings. They will root in 30 to 90 days. Once they have rooted, you can transplant them outdoors.
Question: When are winterberries ripe/mature enough to harvest for propagation?
Answer: The berries will be bright red when they are ripe. At that point, the seeds will also be mature and ready to be planted. They need a period of cold stratification to mimic winter weather before they will germinate.
Question: Why are there are no berries on my Winterberry bushes?
Answer: Oh dear, it sounds like you have all female or all male bushes. Winterberry bushes need both a male and a female bush to make berries. If the flowers are numerous and small, you have males. If they are large and fewer in number, you have females. Once you have determined which sex you have, you can go to your local nursery and by the opposite sex bush so that you will have berries next year.
Question: I planted a Winterberry years ago next to an oak tree. Needless to say, it never grew very much, but once the oak had to be removed, it took off as it was in the sun. Left a large portion of the oak tree, and the vine in the last year has flourished. Do the vines also need a male plant to produce berries?
Answer: Yes, winterberry has male and female plants. If you know that you have a female shrub, you will need a male to pollinate it so that the female will produce berries. If you aren't sure, the difference is in the flowers. The male shrub will have small flowers in clusters while the female shrub’s flowers will be more conspicuous and fewer in number.
Question: Is there a Winterberry fragrance?
Answer: No, the flowers have little to no fragrance.
© 2017 Caren White
Caren White (author) on January 26, 2020:
Caroline, I don't know where you live or your growing zone so I can only give you a general answer. You can plant your winterberry after the soil has thawed in the spring whenever that is in your area.
Caroline McCravy on January 26, 2020:
I have a small winterberry in a quart size pot and it is doing fine outside. When can I put it in the ground.
Caren White (author) on December 13, 2017:
You're welcome! Thanks for reading and commenting.
Jill Spencer from United States on December 13, 2017:
Lovely plant, lovely hub. Thanks for sharing your expertise.
Caren White (author) on December 13, 2017:
The paper towel method will work but the roots may be damaged when you transplant into soil. That's why it's best to start directly in soil. Every time you transplant a plant, you risk damaging the roots. That's what "transplant shock" is. Roots have been damaged or destroyed. Since the roots support the foliage, no new growth will appear until the damaged/destroyed roots have been replaced. Thanks for reading and commenting.
Kristin Marriott from Morrisville on December 13, 2017:
This posting arrived in my mailbox at a serendipitous time, as I am looking to start a winterberry from seed. I put the seeds in a wet paper towel inside of a plastic bag into the refrigerator. Will this paper towel method also work, or do the seeds need to be in soil?
Thanks for the informative post!
Caren White (author) on December 12, 2017:
It's probably a matter of local taste in landscaping whether or not winterberry are commonly seen. Thanks for reading and commenting and Happy Holidays to you too!
Heidi Thorne from Chicago Area on December 12, 2017:
I only see these occasionally in our area, even though they could grow in zone 5. I think it's interesting that they're poisonous to humans, dogs, etc., but not to birds. Ah, nature. Anyway, thanks for sharing another informative hub about some lovely plants! Happy Holidays!