Holly is a beautiful evergreen plant that can grow as a shrub or tree. Native to Europe and Asia and known scientifically as Ilex aquifolium, holly (also known as English holly) is primarily grown as an ornamental plant in gardens for its leaves and berries. A favorite to use as decoration at Christmas time, holly has distinctive leaves that are easily recognized. The leaves are leathery and shiny and dark green in color. The edges of each leaf are wavy and come out to a sharp point on each edge. To add to the decoration aspect of this plant, hollies also produce small clusters of red berries that look very ornamental when paired with the leaves.
The straight species of holly can attain a height of up to 50 feet tall and a width of 30 to 50 feet. Hollies prefer cool, moist locations with well draining soil and are not tolerant of climates that become very hot and dry during the summer months. In the western states of the United States, hollies were able to naturalize amongst the native trees and shrubs after being introduced as seed from birds. Although not considered a noxious weed just yet, holly plants growing wild in Western Washington state are of concern as they compete with the native flora for space and light.
Hollies belong to a group of plants that are known as dioecious. This means that each plant will either produce male or female flowers and only the plant with the female flowers will produce berries. In order to have a holly plant that is full of beautiful berries in time to be cut and used for decorations, the plant must be a female and there needs to be a male holly planted nearby for pollination to occur.
Because this plant is primarily grown as an ornamental, there is a vast array of different varieties that have different leaf shapes and color, habit and form, and berry color. Holly plants can be found with variegated leaves that are white, gold, or yellow, or with leaves that are completely smooth and devoid of all spines or more prickly than a cactus. Berries of selected varieties may also be black, orange or yellow. With different leaf forms, color, and berry color, ornamental hollies will add texture and interest at all times of the year, rather than just December. For those who do not wish to accidentally introduce holly plants into the native ecosystem, choose an ornamental variety that is a male, as it will not produce berries.