American holly is one of a number of varieties of holly available all over the world. Native to the east coast of America, American holly has many of the same characteristics as European holly, the traditional Christmas decoration. The leaves are spiny, green and last year round. Different varieties of American holly have berries ranging from red to yellow in color. They make an excellent addition to your garden, both as a tree and as a source of decoration.
Holly is a very versatile plant. Its different varieties can grow to more than 15 feet tall or be trimmed short as a bush or hedge. Holly takes well to heavy trimming and shaping. American holly tends to grow in a pyramidal shape that starts right from the base of the trunk. Trimming can encourage a shorter, bushy shape, or lower branches can be removed to create a more tree-like profile. This flexibility of shape means holly can be used to fit almost any placement in your garden. However, you will want to prune shorter branches at the base as they do not get enough sun and will die off.
Hollies are best pruned in the winter, which is a wonderful opportunity to collect branches for decorating your home at Christmas. They can be pruned in other seasons. However, if you prune in the spring the berry production for the year will be lost.
The berries of the holly are popular with birds. Consider placing your holly where you can see it from your house so you can enjoy watching them through the winter.
Sun and Soil Requirements
While American holly can grow in shade, to look its best make sure it gets partial or full sun. A holly in shade will produce fewer leaves and berries, and grow more slowly.
Holly trees like slightly acidic soil that is moist but well draining. Standing water or a flood will likely kill a holly after a few days. There are a few varieties of American holly that are very resistant to salt spray, making them excellent coastal plants
Hollies are Dioecious
Most varieties of American holly come in male and female plants. To produce berries, there must be at least one of each within 30 or 40 feet of each other. A ratio of one male plant to 3 or 4 female plants is recommended.
While only the female plants produce berries in the fall and winter, both produce flowers in the spring. The male flowers tend to be sweet smelling while the female flowers are unscented.
There are a few varieties of American holly that are self-fertilizing. If you want just one tree and you want berries, choose a self-fertilizing variety.
Wind and Heat
Hollies suffer wind damage. Wind can drive young leaves into each other, causing holes from the spines. Also, high winds, especially in winter, can pull moisture out of your holly, causing leaf scorch. When possible, plant hollies where something else can form a wind break or put up a burlap wind break in the windy season. Never use plastic for a wind break. Also, anti-transpirant spray can be applied to protect the leaves.
Sun combined with high heat can also cause leaf scorch. An anti-transpirant spray can help protect hollies from the sun. Any holly stressed enough to get leaf scorch is also at risk for a few fungal and insect attacks. The best way to avoid this is to protect your tree in winter and not over water.