With its evergreen leaves and brilliant red berries, holly has traditionally been associated with Christmas decorations. But it also plays an important role in residential landscapes. This versatile shrub is effective in framing the corners of houses, serving as a privacy screen, and enlivening yards with its attractive foliage and bright fruit. With over 400 species of holly, distinguishing between them might seem an overwhelming task. But there are determinations you can make that will point you in the right direction toward identification.
Look for the presence or absence of leaves in winter to determine if the holly is deciduous or evergreen. If there are no leaves in the winter, only bright red berries, chances are good that the holly is a winterberry, or Ilex verticillata. The presence of wet, swampy soil is also a good indication that it is winterberry; this holly thrives in wetlands in eastern Canada, and in the United States east of Missouri.
Examine the leaves for the presence or absence of spines to help you determine holly variety. The Yaupon holly, a Japanese variety, has spineless leaves, while both the dwarf Buford holly and the Carissa holly have leaves that feature a single spine at the end. Most varieties of American holly have between five and 13 spines around the perimeter of the leaves, and a single, pronounced rib in the middle.
Observe the size of the plant for a clue as to variety. The American holly, scientifically known as Ilex opaca, can attain a height of 30 feet and a width of 20 feet, while the English ivy, or Ilex aquifolium, rarely exceeds 15 feet. Dwarf holly plants, which include the dwarf Yaupon holly, Carissa holly, and dwarf Buford holly, rarely exceed 2 or 3 feet in height at maturity.
Examine the holly plant for the presence of berries. While the American and English hollies and the dwarf Buford holly produce brilliant red berries, the dwarf Yaupon and the Carissa holly bear no fruit.
Observe the plant's shape for help in discerning the variety. The American and English hollies, which look similar, can be distinguished by the fact that the American holly displays a more pyramidal shape. If the holly is narrow and conical, with dark evergreen leaves and upright branching, it is probably the Japanese holly known as Sky Pointer.
Examine the glossiness of the leaves for more help distinguishing the American from the English hollies. The English holly features brilliantly glossy, dark evergreen leaves, while the American varieties tend to be duller and paler.