Home landscapes designed to attract birds and butterflies benefit from the addition of a sweetbay magnolia (Magnolia virginiana). Native to the southeastern United States, sweetbay magnolia is a broad-leaf evergreen or semi-evergreen tree in the warmer locations of U.S. Department of Agriculture plant hardiness zones 5 to 10. In cooler locations, sweetbay magnolia is deciduous. Two- to three-inch wide creamy white, cup-shaped flowers are borne in spring or summer and sporadically until late fall.
Sweetbay magnolia produces 3- to 4-inch long cones studded with fleshy scarlet seeds, attractive to many songbird species and woodpeckers. Three- to six-inch long medium green leaves flutter in the breeze, revealing silvery undersides. Evergreen to deciduous, depending upon the climate and cultivar, the leaves and twigs of sweetbay magnolia are slightly aromatic with a spicy fragrance. Leaves are host to swallowtail butterfly larva. Lemon-scented flowers are sporadic, dotting the tree lightly during the blooming period. Useful as a small, multi-trunked courtyard tree, specimen plant or addition to a mixed shrub border, the smooth gray bark of sweetbay magnolia is attractive in the winter.
Native to eastern coastal regions with moist or boggy soil, sweetbay magnolia thrives in humus-rich, acidic soil in sun or partial shade. However, sweetbay magnolia is highly adaptable to home gardens and woodland settings where it is tolerant of different types of soils and grows with various pH levels. In alkaline soil leaves are subject to chlorosis, turning yellow. Amend soil with peat moss before planting sweetbay magnolia to increase soil acidity, and fertilize with a balanced fertilizer blend annually to avoid yellow leaves. This tree is tolerant of air pollution but is subject to injury from salt spray in the winter.
Variants and Cultivars
Magnolia virginiana glauca is a variant of the sweetbay magnolia with more silvery leaf undersides and a pyramidal form. Flowers are scented lemon or rose. Variant Magnolia virginiana australis is evergreen to minus 17 degrees Fahrenheit. Cultivars of this variant include "Henry Hicks" -- a 25-foot tree useful for vertical definition with its wide, columnar form, and "Aiken County" -- with glossy leaves and a globular habit. Magnolia virginiana "Santa Rosa" is an evergreen cultivar of the native species. M. virginiana "Moonglow" is an upright form reaching 35 to 40 feet with a spread of 15 to 18 feet.
Prune in spring to remove wayward branches or to control height. Remove dead or diseased branches. Make cuts back to the trunk or a main branch to preserve the natural form of this tree. Control the size of sweetbay magnolia, if desired, by removing entire branches.
- United States Department of Agriculture National Library: Selecting Shrubs for Shady Areas
- North Carolina State University Cooperative Extension Service: Sweet Bay Magnolia
- The New Western Garden: Magnolia Types
- Missouri Botanical Garden: Magnolia Virginiana
- North Carolina State University Horticultural Research Institute: Propagation of Magnolia Virginiana "Santa Rosa" by Semi-hardwood Cuttings
- Ohio State University Horticulture and Crop Science: Magnolia Virginiana
- Georgia Wildlife Federation: Sweetbay Magnolia
- The American Horticultural Society A to Z Encyclopedia of Garden Plants; Christopher Brickell and Judith D. Zuk
- University of Kentucky College of Agriculture: Magnolia Virginiana Australis
- University of Florida IFAS Extension: Magnolia Virginiana "Henry Hicks"
- Art Wolfe/Digital Vision/Getty Images