Deciduous vs. Evergreen Magnolias

Cold Hardiness

• The most prominent of the evergreen magnolias is the southern magnolia, Magnolia grandiflora, along with its cultivars. These magnolias handle the climates from U.S. Department of Agriculture plant hardiness zones 6 through 9. Another evergreen magnolia is the sweet bay magnolia, Magnolia virginiana, but it retains its leaves only in the warmer, southerly portions of its distribution, including zones 8 and 9. Magnolias such as the umbrella magnolia, Magnolia tripetala, and the cucumbertree magnolia, Magnolia acuminata, are suitable for cooler climates, such as zones 3 and 5 respectively.

Height

• One advantage you have with deciduous magnolia trees is multiple species remain small enough for a landscape with limited space. Of the evergreen varieties, Magnolia grandiflora "Bracken's Brown Beauty" grows to 30 feet, while the rest are considerably larger. Southern magnolias typically reach at least 60 feet tall. Smaller deciduous magnolias that grow less than 35 feet tall include the kobus magnolia, Magnolia kobus, as well as the saucer magnolia, Magnolia x soulangeana, and the star magnolia, Magnolia stellata.

Leaf Size

• Leaf size among the evergreen magnolias ranges from the potentially 8-inch long leaves of the southern magnolia to the 3-inch long leaves that can occur on the sweetbay type. The deciduous magnolias boast one tree among their ranks with the biggest foliage of any tree in North America -- palm trees excluded. The bigleaf magnolia, Magnolia macrophylla, has leaves up to 30 inches long and 10 inches wide. Species such as umbrella magnolia have leaves between 10 and 20 inches in length. However, such large leaves are extremely vulnerable to ripping and tearing during high winds and hailstorms.

Similarities

• Similarities exist between the evergreen and deciduous magnolia trees. All generate aromatic flowers, easily noticeable in the landscape. Most flower before the summer months, with some intermittent blooming occurring when it becomes hot. The fruits produced by the magnolias resemble cones, with the seeds inside usually devoured by wildlife. When the leaves of the evergreen magnolias finally do fall from the tree as new ones replace them, they create the same sort of mess as those of the deciduous types. Magnolia leaves decompose slowly, making frequent cleanup under the tree necessary.