The mulberry tree is a deciduous species known for its edible fruit and rapid growth. Determining the final size depends heavily on the specific species planted and local growing conditions. For homeowners, understanding the mature size is practical, as large trees can cause issues with shade, expansive root systems, and messy fruit drop. The tree’s genetic potential ranges from large ornamental shade trees to small, manageable shrubs.
Size Differences Across Mulberry Species
The size of a mulberry tree is dictated by its species, with the three most common varieties showing significant differences. The White Mulberry (Morus alba), native to China, often grows the largest, commonly reaching 33 to 66 feet tall with a similar spread. Some unmanaged specimens of M. alba can reach heights of 80 feet in ideal conditions.
The native North American Red Mulberry (Morus rubra) is also a large tree, frequently reaching heights up to 70 feet with a comparable canopy width. This species requires substantial space and is typically found in larger landscapes.
In contrast, the Black Mulberry (Morus nigra) is generally the smallest and most practical choice for home gardens. Its mature height rarely exceeds 30 feet, and it often develops a more gnarled, bushier, and spreading habit. Specialty cultivars are naturally much smaller, such as the ‘Dwarf Everbearing’ variety, which stays within an 8 to 12-foot range. The compact variety ‘Charlotte Russe’ can be maintained at about five feet when grown in a container.
Understanding Growth Rate and Lifespan
Mulberry trees have a fast growth rate, especially during their juvenile phase. They can add between one and five feet of new growth annually, depending on the species and environmental factors like water availability. The White Mulberry (Morus alba) is the most vigorous, capable of adding three to five feet in height each year.
The Red Mulberry (Morus rubra) grows slightly slower, averaging two to four feet per year. The Black Mulberry (Morus nigra) is the slowest, typically adding only one to three feet annually, which contributes to its manageable size. Most mulberry trees reach functional maturity and begin producing consistent fruit crops in about 10 to 15 years.
The lifespan of these trees varies significantly and relates directly to their size potential. The Red Mulberry rarely lives beyond 75 years, while the White Mulberry can endure for 100 to 250 years. The Black Mulberry is notably long-lived, with some specimens surviving for 500 to 1,000 years and developing a crooked, gnarled appearance.
Cultivation Practices That Limit Mature Height
Mulberry tree size can be managed through cultivation practices. Pruning is the most effective method to restrict height and spread, and it is best performed during the dormant period in late winter to minimize sap bleeding. Strategic annual trimming can maintain the tree at a height suitable for easy harvesting, such as keeping the canopy under 12 feet.
Training the tree to a multi-trunked, open-center form limits vertical growth and promotes a more horizontal, compact shape. Intensive techniques involve repeated heading cuts, which prevent main branches from extending and result in a dwarfish structure. This process is similar to pollarding, where annual cuts are made to the same point to maintain a specific size framework.
Growing a mulberry in a large container is another size restriction method, as the confined root system naturally slows growth. Training the tree as an espalier—where branches are trained flat against a wall—requires regular pruning to maintain a restricted, two-dimensional form. Simple methods, such as weighing down growing branches, can encourage an umbrella shape and curb the tree’s natural tendency to grow upward.