Bigleaf magnolia at Daniel Stowe Botanical Garden, Gastonia, NC

Bigleaf magnolia (Magnolia macrophylla) is native to the southeastern United States as far north to Ohio (USDA hardiness zones 5-8). A mature tree attains heights of 30 to 40 feet and develops an irregular pyramidal form. In the northern areas the tree is deciduous and semi-evergreen in the southeastern U.S.

Its enormous size foliage makes it a true horticultural oddity, something different for a residential site. Its unusual leaf size relegates planting on woodland sites where weak branches and extra large leaves are protected from ice and wind storms.

It grows in full sun or part shade and prefers a well-drained, acidic sandy loam. An established tree is moderately drought tolerant. Its large leaves decompose slowly and create a litter problem. No serious insect or disease problems bother this magnolia if properly sited.

A tree may take 10 or more years before first blooms form. Goblet-shaped flowers are creamy white, rose-purple at the petal base, and up to a foot across. They open in early summer, mostly high in the tree and mostly hidden within the dense foliage. Up close, flowers are pleasantly fragrant. Fruit is round to cone-shaped, rose-colored, and nearly 3 inches long; they’re unique, persistent, and attract numerous bird species. When cones open, each red coated seed is held by a thin silk-like thread.

Leaves are alternate, simple, 12 to 36 inches long and 7 to 12 inches wide. They’re bright green above and silvery gray below. Petioles are 2 to 4 inches long. Its yellow fall color rarely stands out. Leaves are intolerant of most urban pollutants.

It is sometimes called large-leaved cucumber tree — a reference to cucumber magnolia (M. acuminata), a deciduous magnolia from the eastern US which has cucumber-shaped fruit.  Bigleaf magnolia has round or egg-shaped fruits that bear little resemblance to cucumbers.

Bigleaf magnolia may be purchased from on-line tree nurseries.