So, you want to grow some winterberries.
These shrubs produce those bright red berries you commonly see over the holidays.
They also don’t require much work to grow and are extremely low maintenance.
Plus, they offer plenty of food for wildlife to your yard over the winter.
Ready to plant? Let’s find out what makes winterberry such an awesome plant!
Last updated: 11/10/21.
Guide Contents
Quick care guide: Winterberry
| Plant type | Deciduous shrub |
| Origin | United States, Canada |
| Scientific name | Ilex verticillata |
| Other names | Hollyberry, winterberry, winter hollyberry, false alder, berry bush, fever bush, black alder, alder berry |
| Soil type | Loamy, well-draining |
| Soil pH | 4.5-6.0 |
| Sunlight requirement | Full sun, partial sun |
| Bloom season | Fall, winter |
| Colors | Red, green, yellow, pink, orange, white |
| Max height | 3-20 feet |
| Max width | 15 feet |
| Temperature | -20F+ |
| Humidity | High |
| Watering requirements | Often during summer and fall, let dry between waterings during winter |
| Fertilizer requirements | Low (10-10-10 NPK) |
| Days until germination | 30-90 days |
| Days until bloom | Many years, varies |
| Speed of growth | Very slow |
| Hardiness zones | USDA zones 3-10 |
| Plant depth | As deep as the root ball |
| Plant spacing | 3-7 feet |
| Propagation | Seed, cutting, division, self-pollination |
| Common pests | Birds, deer, raccoons, small animal |
| Common diseases | Powdery mildew |
| Beginner friendly | Yes |
| Care level | Low |
| Uses | Decoration, color, centerpiece, photos, privacy hedge, arts and crafts |
What’s winterberry holly?
Winterberry holly is a gorgeous plant that’s best known for its place in pictures during the winter holidays.
Although it looks like it may be imported, it’s a native plant that grows in acidic swamps, rivers, and ponds throughout the United States.
Winterberry is also found in Canada in similar settings.
The most striking feature of winterberry is the bright red berries growing from the thick bush that holds them in bunches.
With its tiny flowers and blooms, the berries take the spotlight.
This plant is also known as the Canada holly, black alder, and common winterberry holly and is found in the subtropics where the temperatures are warm and humid.
The flowers are usually blocking the tiny flowering blooms covered with dark, lush leaves that have pointed teeth.
English holly, for example, has the signature berries surrounded by leaves that are dark green with a lustrous texture that shines under light.
The leaves are teeth and look threatening (and they are).
On the opposite end, some species have soft teeth with extremely narrow leaves.
There are many different cultivars each with different physical features, so one care guide may not cover them all.
The berries are small drupes that contain seeds. This is their main mechanism for dispersion and propagation. If you cut one open, you’ll see that the seeds can be different colors depending on the species.
Some are gold while others are orange. Most are red.
Regardless, this plant is common as a background on Christmas cards or even as a centerpiece for the table.
Is winterberry poisonous?
Yes, the berries produced by winterberry plants are toxic to humans, dogs, cats, and other pets.
Don’t ingest them and always wash your hands if you make direct contact.
Use gloves and proper PPE to protect yourself when you need to handle the plant.
Although it makes an amazing centerpiece around the home, don’t let it touch any surfaces where food is served.
Is it an evergreen?
No. Wintergreen holly is a deciduous shrub- not an evergreen.
This is what allows it to show off those gorgeous red berries all winter long. This attracts birds and adds some color to any garden.
Where does winterberry come from?
Winterberry (Ilex verticillata) is a holly shrub that comes from the US and Canada.
It’s native to the eastern side of the US, but can be grown all over the States due to the various hardy strains that have been produced over the years.
The bright berries are a signature of this plant.
They range in size, color, and the number produced depending on the strain. The berries last throughout the winter and into early spring.
What is winterberry used for?
Other than being a gorgeous decorative piece for your garden, winterberry holly can also be used for many other purposes.
Here are just some random ideas:
- Background picture for holiday cards
- Background for photos
- Decorative pieces around the home
- Tabletop centerpiece
- Privacy hedge
- Plant/garden border
- Christmas tree decoration
- Wreath decoration
- Bird food
- Small animal food
- Attracting wildlife
- Foundation shrubs
- Shrub borders
- Bird gardens
- Woodland decor
- Special landscaping
The possibilities are limited to just your imagination. This is a versatile plant that’s extremely beginner-friendly.
Just remember that the berries are toxic, so keep it away from people and pets.
Otherwise, what more could you ask for?
Winterberry holly is a pest tolerant plant that takes care of itself every year for you (and the birds) to enjoy.
Where to plant winterberry holly
Choosing the right location is key. You should seek out an area with full sun and well-draining soil.
This plant loves acidic soil and requires it to grow properly. The soil should be between 3-6 pH, ideally between 4-5. If you don’t know your soil’s pH, it’s strongly suggested that you buy a soil meter.
Transplanting it later will be a hassle so it’s efficient to get it right from the start.
If your soil is too alkaline, you can reduce the pH naturally by using peat moss.
Mix the soil with organic peat moss and cover the top 12” of depth with this soil/peat moss mixture.
This should reduce the pH drastically. Test it again to ensure the pH is in the proper range.
Hardiness zone
Winterberry holly is tolerant of temperatures across the US. It does best in zones 3 up to zone 10 depending on the type you’re planting.
Plus, it’s beginner-friendly and does well in cold, acidic environments that resemble its native wetlands.
The plant is also resistant to many pests that would otherwise plague wintertime plants.
Will it grow in shade?
Yes, winterberry holly can grow well in partial sunlight or full sunlight.
How fast does it grow?
Winterberry grows slowly and vertically. Some cultivars can grow horizontally, but only by a few feet.
Most strains grow vertically up to 15 feet in height, so you’ll need plenty of vertical space for it to prosper.
Suckers form readily with dark green narrow leaves that are about 3 inches in length. From spring to fall, the plant is a sleeper with nothing to show.
But once winter comes around, it just may be the only plant in your garden that needs absolutely no special care all winter (and has plenty of color to with it). It can be used as a privacy hedge or just for decoration.
Fall leaves are green or white which will last all season until late fall when the berries start forming.
Some varieties may develop their berries in summer.
How do you take care of a winterberry plant?
Here are some basic tips on caring for winterberry holly.
This section covers common practices to grow winterberry holly.
The plant is beginner-friendly and doesn’t require much maintenance after you get it going.
Soil
Winterberry is native to swamps, ponds, and other wet marshes.
Therefore, they do best in areas that they’re already used to. Wet areas of your garden work best, but you should ensure that there’s still a drainage way to get rid of excess moisture.
This plant will do fine with excess moisture present, but well-draining soil still trumps poorly draining soil which can lead to powdery mildew and other plant fungi.
Most winterberry plants are easy to grow and require little maintenance so that even beginners can grow them without any problems. They’re winter hardy, pest free, and disease-free.
Plus, they’re a perfect plant for winter because they thrive while others wilt.
If you need some color in your garden throughout the entire winter, winterberry holly is a top contender.
Choose acidic soil that’s well-draining. Add any supplements or plant food while mixing.
Winterberry isn’t picky about its soil as long as you provide it some high quality, nutritious substrate so it has something to feed on all year.
Both light and heavy soils do well- just use loamy acidic soil with high-quality organic materials. Avoid high alkalinity or neutral soils.
Temperature
Winterberry can tolerate a wide range of temperatures so there’s no need to worry about extreme heat or cold snaps.
Unless you live in the extremes.
Winterberry can handle temps ranging from -20F to typical summertime temperatures. These are hardy all around.
Humidity
Similar to temperatures, winterberry can tolerate a wide range of humidity conditions.
There’s generally no need to do anything about the humidity levels outside.
If there are extended periods of dry weather, consider raising the humidity around the plant by watering or creating a microclimate.
Watering
Watering is simple- add water when the soil dries out but only the top 1-2”.
Avoid overwatering. Winterberry will tolerate excess moisture, but it’s advised to not overwater because this can lead to rot problems at the root level.
Transplants have a slightly different watering regimen. When you first plant transplants, add water daily until you see new plant development.
Once you notice this, reduce watering and let the soil go dry between each watering session.
Keep to this schedule for a few weeks until the plant is established. Then go back to regular watering as mentioned above.
During the summer, use more water and make sure to monitor the soil water saturation between waterings.
Winterberry holly doesn’t tolerate drought and excessive dehydration will lead to failed blooms, which means no berries will form.
If you want to reduce watering, you can add some organic mulch to the top layer of soil to help retain moisture.
You can also use moisture-retaining soil as a base substrate.
Plant food/fertilizer
There’s generally no need for any additional fertilizer unless you notice that your soil is neutral or above pH 7.
You can add some acidic fertilizer to lower the pH and make it more acidic.
If your winterberry grows extremely slow, add some 10-10-10 NPK food in the spring to supplement.
Winterizing
During the winter, keep the roots protected from moisture.
Wetness at the root damages the root system and can lead to rot, fungus, or other nasty winterberry problems.
Similar to wintering other flowering plants like baneberry or dewberry, you can add straw mulch, bark mulch, or even just plain compost foliage to keep it free of water.
This will help keep the roots warm and insulate them from temperature swings.
If you live in a zone that’s prone to cold snaps, consider adding extra inches of mulch. Utilize microclimates where possible.
How to prune winterberry
Flowers and subsequent berries only will develop on new growth, which is done by pruning.
The shrub should be pruned during the spring before you spot any new leaves forming.
Prune up to 30% of the branches completely. And repeat this every year. Cut the oldest branches first and cut them down to the soil level.
Flowers and subsequent berries only will develop on new growth, which is done by pruning.
The shrub should be pruned during the spring before you spot any new leaves forming.
Prune up to 30% of the branches completely. And repeat this every year. Cut the oldest branches first and cut them down to the soil level.
Whatever the case, keeping your plant well maintained over time pays off with a healthy, robust, and upright plant that’s sprouting with fresh red berries. If you don’t prune, the plant begins to sucker quickly.
When to prune
This is completely up to you. If you want it to grow like weeds and max out its height, then do it.
For the maximum amount of berries to form, you can reduce pruning and limit it to just damaged or wilted leaves and branches.
Any branch that’s drooping or has spent leaves can be pruned off.
Leaving the branches unpruned will maximize berry yield since the buds grow on older branches. If you cut it off, it eliminates any chance of berry production.
How to propagate winterberry holly
This is one of the most important sections to understand because it’s the only way you can keep your winterberry holly going year after year. So read up.
Winterberry holly is dioecious, which means that male and female plants are separate. The same plant never contains both male and female flowers.
This means that planting a male next to a dozen females or so should be ideal.
They must be within 50 feet of each other for the best chances of pollination. Only the females will produce berries, thus you need both to pollinate.
First, there are four primary methods to propagate winterberry.
Depending on your circumstances and experience level, choose accordingly.
- From seed
- From cuttings
- Through division
- From a transplant
Let’s dive into each one and see how you can utilize them.
Growing from seed
This is not my recommended method because it simply takes way too long and requires too much work.
If you’re interested in getting your winterberry going from seed, follow the directions on the seed packet as the cultivar you’re growing varies in direction.
Propagation through cuttings
Winterberry holly can be propagated through the plant cuttings.
This is the least required effort out of them all, so no wonder it’s the most popular.
All you need to do is take some plant cuttings from both parent plants- one male and one female.
This will ensure you possess all the parts you need for future propagation. A male plant and a female one will allow you to keep producing berries annually.
To cut, use a sharp and clean pair of shears. Cut the softer areas of the plant where new growth is seen on established male/female counterparts.
You’ll need about 3” of cuttings, as many as you want, from each plant. Remove all the leaves and foliage at the older part of the wood, leaving only the new growth at the end of the piece.
Clean the cutting by using a spade and scrape the debris stuck on it.
At this point, you should have a few pieces of softwood from each winterberry.
Next, prepare the cuttings for planting. Get small plant containers and fill them up with a mixture of perlite and peat moss.
Keep it moist by spritzing it. Add any supplements you like at this point, such as rooting powder or plant hormones. Dip the cut, exposed ends into it.
When you’re all set, stick the softwood into the peat moss mixture.
Repeat the process for each cutting. Place the incubator containers in partial sun and use a cover to hold moisture.
Keep the substrate and cuttings wet by spritzing them daily.
You should see new growth after 1-2 months. It’s time to acclimate!
Find an area in your yard that has direct sunlight for at least 6 hours daily.
Consider planting them in a microclimate that is free of strong winds, drafts, and floods.
Leave them outdoors during the day and let them get more and more exposure to the elements.
Start with partial shade, then move to full sun over a year. You can use a greenhouse or partial shade covers to limit sunlight exposure.
Eventually, you’ll want to move up to at least 8 hours of sun every day.
Be patient during this part of their life. It can be annoying to constantly worry about them, but once they’re established, they’ll produce for you for years. It’s almost like raising real-life kids.
After a year or so, the cuttings will have formed complex root systems and many layers of foliage. You can start translating them into the soil.
When you transplant them to their new permanent home, use well-draining, acid soil. The best time to do this is in early fall, right after the long summer.
Be sure to plant at least one male with your female winterberry plants at most 30-50 feet from one another. If you don’t, you’ll have to manually pollinate come spring.
Don’t reuse the same soil they grew up in when they were raised indoors. This helps eliminate any possible fungus or bacteria that may be in the soil.
How to propagate by division
Planting winterberry by division is also extremely easy.
Just harvest a few suckers from each male/female pair and transplant them into small containers with well-draining, acidic soil.
A 10” planter should be enough for starters.
Add any supplements if you wish, and consider using peat moss to lower the overall pH.
Water daily to keep the soil wet, but don’t let it dry out between waterings. The plant needs to become established first before you go hardcore and let it go dry.
Continually do this and let the plant acclimate to the outdoors. The process is pretty much the same as propagation through cuttings.
You can also use a microclimate setup outdoors to control the dangerous elements.
Keep the plant inside its container until you see new growth. Then you know it’s time to move them into the garden with a transplant.
If you’re using biodegradable pots, you can just dig out a section in new soil and put the pots int here.
Keep the holes about 5 feet apart and plant the winterberry about 8” deep.
Add plant supplements if needed. Use straw mulch or leaf litter to keep the plant warm over the winter.
Water daily and let the soil go barely dry.
Keep watch over it as it adjusts to its new home in your garden.
Make sure you plant at least one male within 30-50 feet of your female plants. This will allow self-pollination.
Note that you can just leave the plants in their containers as well. If you don’t want to translate them yet, you can do a delayed transplant.
Let them stay in their planters until next spring. Wate