Evergreen Southern Magnolia - Magnolia Grandiflora - How to grow Bull Bay Magnolia

Southern Magnolia is a native American with an original range from west Texas, east through the southern halves of Mississippi, Alabama, Georgia and South Carolina to parts of North Carolina, including northern Florida. Often found near the edges of bodies of water, it is associated with the native species that prefer that same milieu, like Tupelo, Water Oak and Sweetgum. It is one of several native Magnolias that were introduced to Europe early on in our country’s history: Mark Catesby took it back to England in 1726. It was also adopted into French horticulture at that time by explorers ‘mining’ the Louisiana territories. In the wild, the tree goes slowly to over eighty feet (the national champion is 98 feet tall and 90 feet wide in Jones City, MS), but under cultivation you can expect a smaller specimen. Given extra water and fertilizer, one can also encourage its rate of growth to almost ‘fast.’ It is cylindrical to conical in shape, sometimes spreading into an uneven open-canopied look. The evergreen leaves are dark green and glossy on the upper side and either brown or light green, sometimes silver underneath and somewhat pubescent, a horticultural term for ‘hairy’ or downy. The leaves on the inside of the canopy drop in spring and fall, covering the ground with the large (to 6 to 10 inches long and three to five inches wide) leaves. The real show for this plant is summer, when in June it begins to flower. The very large flowers(hence the species name: grandiflora) appear on the plant, looking like white birds perched on the ends of branches. Wonderfully fragrant (“…better than the best perfume” writes Michael Dirr), these creamy flowers, up to a foot in diameter, attract every sort of pollinator, from honey bees to butterflies. This fragrance is redolent of the South, and evoke the good and bad thereof: hot days, soft summer nights, barbecue on the breeze, the itch of chiggers near the waistband, a banjo being strummed in a desultory way with a whiskey-roughened voice singing about days gone by. When choosing a plant at the nursery, and I urge you to patronize the locally-owned nurseries, check for fragrance and also for other flowering traits. There is great variability between wild seedling-grown Bull-bay Magnolias and the many cultivars. The cultivated varieties will bloom at a much younger age, and will bloom more reliably all summer long. There are dozens of named varieties of the species, some more dwarf and earlier flowering, some with more cold hardiness, and others with a more columnar form. One can’t beat the plant for use as an evergreen specimen, for cut flowers and Christmas cuttings (both leaves and bright red seed pods) or to screen a view of the neighbor’s dog run or parts-car storage area. While it is not hardy above Zone 6 (even then some protection from winter wind and sun is a good idea), it is a knock-dead addition to the landscape. The Bull-bay Magnolia here at the Marsh Botanical Garden is protected by a building. As with all broad-leaved evergreens, good soil drainage and heavy mulching will help get them through the winter. It’s not so much the cold temperatures as the fact that water in the soil freezes, causing the plant to undergo drought stress.