An American Holly Tree can grow 40-60 feet tall and 20-30 feet wide or they can be pruned into a hedge. They grow well in full sun to shade. American Holly trees are resistant to mildew, insects, disease, drought and are easy to prune or shear. American Holly Trees do require male and female plants to produce the beautiful red berries in Fall and Winter. So you need to buy 3 or more to assure they mate.
"When the Pilgrims landed the week before Christmas in 1620 on the coast of what is now Massachusetts, the evergreen, prickly leaves and red berries of American holly (Ilex opaca) reminded them of the English holly (Ilex aquifolium), a symbol of Christmas for centuries in England and Europe. Since then the American holly family, also called white holly or Christmas holly, has been one of the most valuable and popular trees in the Eastern United States for its foliage and berries, used for Christmas decorations, and for ornamental plantings."