The size of a Robin red Holly tree, or Ilex verticillata, can vary depending on various factors such as growing conditions, pruning, and the specific cultivar. Generally, this native plant can range in height from 6 to 15 feet (1.8 to 4.6 meters), with a spread of 6 to 12 feet (1.8 to 3.7 meters).
In optimal conditions, where the winterberry is grown in moist, acidic soil and receives full sun to partial shade, it can reach its maximum potential size. However, it is important to note that these plants are adaptable and can tolerate a wide range of soil conditions, including wet or poorly drained areas.
When it comes to pruning, the size of the winterberry can be controlled to some extent. Pruning can be done in early spring before new growth starts, and it is typically done to maintain a desired shape or size, remove dead or damaged branches, and promote overall plant health. By selectively removing branches, you can manage the size of the tree and prevent it from becoming too large for your garden space.
There are also different cultivars of Ilex verticillata available, some of which have a more compact growth habit. For example, the ‘Winter Red’ cultivar is known for its dense and rounded form, reaching a height and spread of about 6 to 10 feet (1.8 to 3 meters). On the other hand, the ‘Winter Gold’ cultivar can grow slightly taller, reaching a height of around 8 to 15 feet (2.4 to 4.6 meters).
Personal experience: In my own garden, I have a Robin red Holly tree that has been growing for several years now. When I initially planted it, it was a young sapling, only about 2 feet tall. Over the years, it has steadily grown, and now it stands at approximately 10 feet in height and has a spread of around 8 feet. I have pruned it annually to maintain its size and shape, and it has been a beautiful addition to my winter landscape, especially when the bright red berries emerge.
The size of a Robin red Holly tree can range from 6 to 15 feet in height and 6 to 12 feet in spread. Pruning and specific cultivars can influence the ultimate size of the tree, allowing for some control over its growth.
