Magnolia is the common name of more than 80 species of trees and shrubs, deciduous and evergreen.
Many magnolias are spectacular in blooming season bearing probably the largest flowers of any cultivated tree. Flowers range from white through yellow and pink to purple.
Magnolias are not especially graceful in form but the astonishing spring transformation from naked branches to a mass of gorgeous, fragrant flowers never fail to win admiration.
Magnolias are native to North and Central America and Asia.
Evergreen magnolias such as Southern Magnolia and Sweet Bay Magnolia are not as hardy as deciduous kinds. Evergreen magnolias grow best in warm-winter temperate regions. Some deciduous magnolias such as Magnolia acuminata are hardy to Zone 4.
From Asia come slow-growing, dwarf species and hybrids such as Magnolia kobus, stellata, and soulangeana. These varieties blossom before the leaves and are some of the most striking and useful garden and landscape trees. In view of their early blossoming habit, they are best placed against an evergreen background.
Most magnolias thrive in rich porous soil that is moderately moist, preferring sandy or peaty loam. They are difficult to transplant and must be carefully balled and wrapped and trampled when reset to avoid breaking and bring the roots.
Move native magnolias just as growth begins. Move Asiatic species and hybrids when in bloom as the root are tender and will not health except when the plant is growing.
Magnolias must be pruned during the growing season as dormant trees do not easily heal their wounds.
Types of Magnolia
Evergreen magnolias. This group grows best in mild-winter regions. The best known evergreen magnolia is the southern magnolia, Magnolia grandiflora. A second evergreen is M. virginiana; it is smaller than the southern magnolia and hardier. Two hybrids of the southern and sweet bay magnolia are M. ‘Freeman’ and M. ‘Maryland’ which are similar to the southern magnolia but hardier.
Deciduous magnolias with saucer flowers. This group includes M. soulangiana and its many cultivars, also yulan magnolia (M. denudata), and lily magnolia (M. lilifora). Deciduous magnolias grow best in cold winter regions; they do poorly in hot, dry regions. Oriental magnolias are included in this group but they can suffer frost damage; included are M. campbellii, M. dawsoniana, M. sargentiana robusta, and M. sprengeri.
Deciduous magnolias with star flowers. This group includes M. kobus, M. stellata and its varieties–the star magnolias, and M. salicifolia. All are cold-hardy and slow growing. All are early blooming.
Other magnolias. This group includes magnolias that bloom as leaves appear or after the leaves unfurl; these are generally foliage plants or shade trees. Among this group are M. acuminata and M. hypoleuca which have inconspicuous or small flowers; and M.fraseri and M. macrophylla, both are medium-size trees with large leaves and flowers.
Best Known Magnolia Varieties
- Southern magnolia, Magnolia grandiflora: to 90 feet 927m) tall and 55 (16.5m) wide; native to the southern United States; a pyramidal evergreen tree with oval 10-inch (25cm) long leaves that are glossy dark green above, downy below; fragrant, waxy, creamy-white flowers from late spring to midsummer; followed by red strawberry-like fruit; Zones 7-10.
- Kobus magnolia, Magnolia kobus: to 25 feet (7.5m) tall and nearly as wide; a deciduous tree native to Japan; pyramidal at first matures to rounded form; white six-petaled flowers in mid spring, followed by pink fruit; Zones 4-8.
- Saucer magnolia, Magnolia x soulangiana: to 20 feet (6m) tall and slightly wider; a deciduous tree, often multi-stemmed form; saucer-shaped white or rosy-purple flowers in early spring; followed by greenish fruit; Zones 5-9.
- Star magnolia, Magnolia stellata: to 15 feet (4.5m) tall and nearly as wide; deciduous shrub or small tree much-branched, rounded, compact habit; white flowers with strap-shaped petals in early spring; followed by pink fruit; Zones 5-9.
- Sweet bay magnolia, Magnolia virginiana: to 60 feet (18m) tall and 30 feet (9m) wide; shrub or small tree, evergreen in warmer portions of the range, deciduous in colder regions; fragrant creamy white flowers from late spring to early fall; followed by red conical fruit; Zones 5-9; plant in moist, humus-rich, well-drained soil, partial shade.
Get to Know Magnolias
- Plant type: Evergreen and deciduous trees
- Growing Zones and range: Zones 5 to 9
- Hardiness: Hardy to Zone 5
- Height and spread: Varies greatly by variety; see list above
- Foliage: Elliptical to ovate, leathery green leaves with brown furry undersides
- Flowers: Cup and saucer-shaped flowers from white and cream to rosy purple depending on the variety
- Bloom time: Deciduous magnolias bloom in spring; evergreen magnolias bloom in summer
- Uses: Specimen, lawn tree depending on the variety
- Common name: Magnolia
- Botanical name: Magnolia
- Family: Magnoliaceae
- Origin: Asia to North America
Where to Plant Magnolia
- Plant magnolias in full sun to partial shade.
- Grow magnolias in deep, loamy, slightly acid soil.
- Shelter magnolias from cold winds.
- Magnolias prefer a soil pH of 5.0 to 6.0.
When to Plant Magnolia
- Transplant balled-and-burlapped or container-grown magnolias in spring.
- Container-grown trees planted in spring do better than balled-and-burlapped ones.
- Sow ripe seeds in spring; magnolias raised from seed may take 30 years to flower.
Planting and Spacing Magnolia
- Space trees from 20 to 60 feet apart depending on the vareity
How to Water and Feed Magnolia
- Keep the soil evenly moist; mulch to conserve soil moisture
- Fertilize magnolias by spreading aged compost to the dripline at least once a year.
- Stake young trees at planting time.
- Shake snow from the branches of evergreens so that the weight does not break branches.
- Mulch trees with aged compost in drought conditions.
- Do not underplant around magnolias; weeding or cultivation can damge tree roots.
- Prune magnolia after flowering only as necessary to shape the tree.
- Many deciduous varieties will be slow to heal if pruned while dormant.
- Cut back straggly plants and remove dead wood in late summer or after flowering for deciduous species and in spring for evergreens.
- Hard prune only mature specimens in spring.
Magnolia Common Problems
- If scale insect attack leaves will yellow; prune out badly infested growth and spray the tree with horticultural oil.
- Early spring-blooming magnolias may have flowers spoiled by late frosts.
- Layer magnolias in spring.
- Remove seed from its covering in late summer and sow in fall. Magnolias grown from seed may take 30 years to flower.
- Take greenwood cutting of deciduous varieties and semi-ripe cutting of evergreens.
- Layer plants that produce strong shoots close to the ground.
- Graft magnolias in winter.