How to Grow Winterberry Holly

Close up of winterberry holly shrub
David Beaulieu

Gardeners in northern climates are faced with a challenge in keeping the landscape interesting when the last of the autumn flowers and colorful fall foliage have faded. Winter is a time when many gardeners resign themselves to a landscape that will be a bit dreary until next spring, spending their time planning next year's garden. But if your landscape has been well planned, winter need not be a time of colorlessness. And now might be a great time to consider new plants that might change the entire nature of the winter landscape for future seasons.

Winterberry, a deciduous holly shrub that is native to the eastern U.S., can be a great addition to the landscape, as it produces bright red berries that persist through the entire winter and into spring. Not only do the bright berries add important color to winter landscapes, but they also lure in colorful birds that love to feed on the prolific red berries.

Description

Unlike other familiar holly shrubs, winterberry is a deciduous shrub. Although one might view this as a drawback, it proves to be a beneficial trait, since it allows the exciting display of red berries to come to the forefront as winter arrives. All the attention is drawn to the plant's fruit, with no foliage to obstruct the viewer's vision.

Winterberry is a slow-growing, shrub with a rounded upright growth habit. It typically grows 3 to 15 feet tall and readily suckers to form large thickets. The leaves are dark green and elliptical, about 2 to 3 inches long. Fall color is usually not impressive, although some years may see the foliage turn an attractive maroon color. Fairly plain greenish-white flowers appear in spring, which, if properly pollinated, produce a dense crop of 1/4-inch-diameter of bright red berries in late summer and fall.

Botanical Information

Winterberry (Ilex verticillata) is native to eastern Canada and the entire eastern half of the U.S. It can be used as a landscape plant in USDA hardiness zones 3 to 9, making it one of the most versatile of shrubs. Other common names for winterberry include black alder, false alder, and fever bush.

Winterberry is a dioecious plant, which means there are separate male and female plants. Because only fertilized female plants will produce the wonderful display of berries, it is crucial that there be at least one male winterberry plant in the area to allow for cross-pollination. Generally, a single male shrub can pollinate 6 to 10 female shrubs.

The native species can do well in landscape plantings, but there are many excellent cultivars that produce showier flowers and larger, more plentiful fruit.

Landscape Uses

Winterberry is one of the rare deciduous shrubs that provide good year-round interest in the garden. It is normally planted in masses or groups for shrub borders, as foundation shrubs, in native woodland gardens, or in bird gardens.

Winterberry is notable for being attractive to a variety of birds and other wildlife. When planting it, make sure you are comfortable with inviting animals such as these into your landscape:

  • Bluebirds
  • Robins
  • Catbirds
  • Mockingbirds
  • Cedar waxwings
  • Deer 
  • Raccoons
  • Mice 

The berry-laden branches of Ilex verticillata are prized by arts and crafts enthusiasts for use in such items as floral arrangements, winter window boxes, wreaths, and kissing balls.

Historically, winterberry had medicinal uses. According to Ally Robertson, the Native American use of Ilex verticillata as medicine is the source of one of the common names, fever bush. She notes that native Americans also "used the bark to heal cuts and bruises."

Growing Tips

In nature, winterberry shrubs typically call wetland areas home, although they can be successfully cultivated elsewhere, as well in your yard. However, homeowners who have areas of their landscapes plagued by wetness can take advantage of this shrub's native predisposition and plant it in such areas, where little else will survive.

Winterberry holly prefers acidic soils. It can be grown in partial shade or full sun, but locating your bush in an area with more sunlight will increase berry production. The native species can grow anywhere from 3 to 15 feet tall, and nurseries generally sell several different cultivars, each with its own height and width specifications.

Because the flowers (and resulting berries) appear on new growth, this shrub should be pruned to shape in early spring, just before new growth appears. Pruning is required with these shrubs since they not only grow tall but will sucker profusely if not controlled. Remove up to (but no more than) 1/3 of the branches each year. Target the oldest branches; prune them down to ground level.

If you don't have the time for such pruning duties, make sure to choose one of the dwarf cultivars.

Recommended Cultivars

Planting one of the many good cultivars may be preferable to planting the native species since the growth characteristics are often preferable to the native form. Buying from a nursery can also ensure that you get at least one male plant, necessary for pollination and production of berries.

  • Ilex verticillata 'Oosterwijk' is a Dutch cultivar noted for branches that work well in floral displays. This shrub's branches hold their color and berries very well in flower arrangements. This cultivar grows 4 to 6 feet in height.
  • Ilex verticillata 'Winter Red' is a multi-stemmed shrub that produces its red berries in an, especially vigorous abundance. Mature plants grow to 8 to 9 feet in height.
  • Ilex verticillata 'Cacapon' has attractive, dark glossy green leaves and compact branching. Mature plants are 6 to 8 feet in height, with an appealing rounded growth habit.
  • Ilex verticillata 'Red Sprite' is a great low mounded shrub that grows to 3 to 5 feet in height. It works well as a low hedge plant or in mass plantings, as its branches remain dense right down to ground level.
  • Ilex verticillata 'Winter Gold' is a yellow-berried sport of 'Winter Red'. The berries are pinkish-orange, growing lighter as they age. The shrub grows 5 to 8 feet in height.
  • IIex verticillata  'Aurantiaca' is another color variation, again with bright pinkish-orange fruit. It grows 6 to 8 feet in height.
  • IIex verticillata 'Berry Poppins' is a great dwarf version that grows to only 3 to 4 feet in height.
  • IIex verticillata 'La Have' is another good dwarf shrub, topping out at 3 feet in height.

Problems

Winterberry suffers from almost no serious insect or disease problems. Occasional disease problems include leaf spots and powdery mildew.

Winterberry does best in acid soils, and when planted in neutral or alkaline soils it can be susceptible to chlorosis (yellowing of leaves) and may even die.

Somewhat surprisingly for a plant that produces berries that attract birds, the plant is actually mildly poisonous to some animals. The ASPCA observes that the leaves and berries are toxic to cats, dogs, and horses.