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Scientific: Magnolia grandiflora
Common: southern magnolia, bull bay, evergreen magnolia
Family: Magnoliaceae
Origin: Lowlands of the southeastern United States, eastern North Carolina to central Florida and west to eastern Texas at elevations up to 400 feet.

Pronounciation: Mag-NOL-ya gran-di-FLOR-a

Hardiness zones
Sunset
4-12, 14-24, (13 in mesic landscapes with surrounding green space)
USDA 7-11

Landscape Use: Accent specimen tree for mesic landscapes. Otherwise, commonly used as a streetscape tree in mild maritime, coastal areas of central and southern California, though this use is a recipe for premature tree death in Phoenix.

Form & Character: Young trees are typically pyramidal in shape. Older trees are more broad and spreading. Southern magnoolia trees have a formal, mesic, antebellum character.

Growth Habit: Southern magnolia is an evergreen, woody, perennial broadleaf tree that is a moderately slow grower, eventually 25- to 50-feet tall in the Phoenix area, but larger in the southeast United States. Older trees develop a fluted base with the ridges corresponding to the attachment of major lateral roots.

Foliage/Texture: Leaves glabrous with a thick, waxy adaxial (upper) cuticle, prominent central vein, ovate to 8-inches long or less. Some clinal variants have leaves that are a rich copper brown tomentose on the abaxial side (brown backs verses green backs). Southern magnolia trees are generally coarse textured.

Flowers & Fruits: Wonderfully aromatic, large white perfect flowers to 6-inches across. Fruits are cone like with many indehiscent, bright red seeds.

Seasonal Color: Southern magnolia trees flower in mid to late spring (April to early June).

Temperature: Tolerant to 107oF, however higher temperatures (yes folks, in Phoenix this is a common occurance during June, July and August) typically cause foliar yellowing and trunk sunscald injuries.

Light: Full sun to partial shade. An eastern exposure or amongst and expanse of green vegetative cover is best in Phoenix. Avoid western exposures or sites with reflected radiation due to sunscald injury.

Soil: Tolerant of most soil conditions, though would prefer slightly more acid soil than what occurs in the Phoenix metropolitan area. Some leaf chlorisis occurs during the intense heat of summer.

Watering: Regular irrigations a must, especially in summer!

Pruning: Depends on use, though generally less than anticipated. Allow canopy base to extent to ground if possible. Somewhat prone to trunk sunscald.

Propagation: Seed or semi-hardwood stem cuttings harvested in May.

Disease and Pests: None

Additional comments: Southern magnolia is an old fashioned and truly elegant evergreen tree. It is the aristocrat of landscape trees that is best used in large greenspaces where minimal crown elevation pruning is necessary. It is commonly seen as an ornamental tree in warm temperate and subtropical regions around the world. Check out these brownback southern magnolia trees growing as shade-providing street trees in Istanbul, Turkey. Florists use the dried leaves in arrangements. There are many named cultivars having different leaf morphologies (with or without brown tomentose leaves on abaxial side) and growth forms.

Some notable southern magnolia cultivars include: