A symbol of the American South, the southern magnolia (Magnolia grandiflora) boasts large glossy green leaves with rusty, fuzzy undersides that persist year-round. In spring and summer fragrant white blossoms, 8 to 12-inches in diameter, dot the canopy followed by cone-like fruits with red seeds. This impressive tree with a noble shape grows 60 to 80 feet tall and 30 to 50 feet wide.
A native of the American Southeast, the historic habitat range of the southern magnolia extends from eastern North Carolina south along the Atlantic Coast to the Peace River in central Florida. It then goes westward in a wide band across the southern half of Georgia, Alabama, and Mississippi, and across Louisiana into southeastern Texas. According to the U.S. Forest Service, this tree is most prevalent in Louisiana, Mississippi and Texas.
The natural habitat of this tree is limited by temperature and rainfall regimes in the southern United States, even though in garden settings southern magnolia is quite adaptable. It grows naturally where winter temperatures rarely dip below 15 degrees F and summer highs do not exceed 100 degrees, making the annual growing season no less than 200 to 210 days. Across its native range rainfall varies from 40 to 80 inches per year, which occasional droughts in summer and autumn typically being the driest time of year.
Southern magnolia populations prosper where the native soils are loamy and moist with abundant fertility and organic matter, such as along streams and near swamps. It also grows in more upland locations where forest or grass fires do not occur. This tree can tolerate only short periods of flooding over its root systems. Naturally it is found just outside of the usual floodwater reaches along river courses and swampy depressions.
Across the American Southeast, no part of its natural range is higher than 500 feet in elevation according to the U.S. Forest Service. In fact, most of it is less than 200 feet and in coastal areas within its range the trees occur under 100 feet above sea level. In the northern sections of the habitat range in Georgia and Mississippi, it is found at elevations of 300 to 400 feet.
Associated Forest Plants
Rarely is southern magnolia seen growing as a large grove within its native range. It usually is found in association with other upland tree species in scattered numbers. Southern red cedar, cabbage palm, live oak, swamp chestnut oak, tupelo and sweet bay are trees often seen in a mixed variety among southern magnolias. Occasionally beech, sweetgum, hickory, tulip poplar and other oaks intermingle in the forests.
Understory plants, those growing in the shadows of the southern magnolia's branches, include flowering dogwood, beautyberry, strawberry bush, and southern bayberry. Rambling vines and climbers seen in this tree's habitat include Virginia creeper, muscadine grape and poison ivy.
The red seeds of magnolias that ripen by early autumn drop to the forest floor and are eaten by squirrels, opossums, quails and turkeys.