Culture
Best grown in rich, moist, well-drained soils in full sun to part shade. Best in full sun. Prune in late fall or winter to avoid bleeding. Tolerates heat, drought and a somewhat wide range of soils, including alkaline ones. Shallow rooted.
Noteworthy Characteristics
Morus alba, commonly called white mulberry is native to China. It is a rounded, fast-growing, deciduous tree that typically grows to 30-50’ tall and as wide. It usually develops a wide-spreading crown with age. The leaves of this tree have been used in China since at least 2600 B.C. as the primary diet for silkworms used to make silk. Trees were introduced into North America in colonial times in an effort to establish a silk industry. Although the industry never took hold, the trees did take hold and have over time escaped cultivation and naturalized in fields, waste areas, forest margins and along roads throughout much of the U.S. This tree has also been planted in various areas for erosion control and windbreaks. White mulberry is usually dioecious (separate male and female trees), but sometimes is monoecious. Small yellowish-green flowers in drooping catkins bloom in spring (March-April). Fertilized flowers on female trees are followed by sweet, edible blackberry-like fruits (cylindrical drupes to 1” long) that mature in June. Fruits ripen to white or pink, but sometimes to darker reds or purple-blacks. Fruits are loved by birds. Glossy, rounded, usually 2-3 lobed (but sometimes unlobed), dark green leaves (to 8” long) have serrate margins and uneven (sometimes cordate) bases. Glossy leaf surfaces distinguish this tree from red mulberry. Fall color is an unattractive yellow (sometimes green, yellow and brown).
Genus name comes from the Latin name.
Specific epithet comes from the Latin word meaning white in reference to fruit color.
‘Pendula’ (sometimes called weeping mulberry) is a dwarf, weeping cultivar that typically grows to only 6-10’ tall. It is typically top-grafted to a species tree, with its somewhat gnarled branches weeping to the ground. The male version of this weeping tree is M. alba ‘Chaparral’.
Problems
No serious insect or disease problems. Borers may be a problem particular in the South. Whiteflies mass on some trees. Bacterial blight may kill foliage/branches. Coral spot cankers may cause twig dieback. Bacterial leaf scorch, powdery mildew and root rot may also occur. Watch for scale, mites and mealybugs. Messy fruit may be a concern.
Uses
Many gardeners do not consider this tree to have ornamental or fruiting interest. The fruit and resulting bird droppings are messy and will stain pavements, automobiles and areas around the home. Stains may also be unwittingly brought indoors on the bottom of shoes. The non-fruiting male version (M. alba ‘Chaparral’) is a better selection for residential placement, with the weeping foliage having some ornamental interest.