Broussonetia is a genus of flowering trees native to Asia and the Pacific Islands. The species B. papyrifera or paper mulberry is probably the most well known in this small genus, which contains about four known species. Paper mulberries have historically been used in the production of paper and cloth and they have also been established as ornamentals in many regions of the world. Nurseries sometimes carry Broussonetia seedlings and can order them by request from customers.
Members of the Broussonetia genus are deciduous, producing simple to lobed leaves, often on the same tree. The flowers are globe shaped and reddish in color, maturing to small red fruits. Broussonetia species readily reseed themselves and can also grow from cuttings. They grow to variable heights and the paper mulberry is a popular ornamental cultivar and specimen planting for some gardeners.
These trees are adapted to climates between United States Department of Agriculture (USDA) zones seven and 11. They are hardy and very durable, although their shallow root system can make them vulnerable to high winds. In regions with stormy conditions, large trees may be blown over in stormy months. These trees grow rapidly, compensating for potential losses in the winter season, and also put out suckers around their bases, allowing trees to thrive after the main trunk falls in a storm.
In several regions, Broussonetia is so well naturalized that it is classified as an invasive species. The same traits that can make it a good choice for the garden can become a problem when the plant escapes into the surrounding natural environment. Rapid growth can allow a Broussonetia to overwhelm native plants in the region, for example, and the trees will spread readily once they are established. The suckers can also pose a problem, as simply cutting trees down will not eradicate them, since the suckers can return in the following year.
People interested in growing Broussonetia species will need to work the soil in a sunny to partially shady area of the garden to create an area of rich, moist soil. When seedlings are planted, they should be watered well and allowed to dry out between waterings. Fertilizer given approximately once a month will help trees stay healthy and promote the development of a sturdy root system. Pruning can be used to control the shape and size of a tree, if desired, and trees can be grown together to create a windbreak or privacy screen.
