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Korean Mountain Magnolia

Magnolia sieboldii (mag-NO-lee-ah see-BOLD-ee-eye)

Family: Magnoliaceae Non-native Understory (15-40 ft)

The Oyama Magnolia is a large deciduous shrub or small tree with a spreading form reaching a mature height of about 26 feet and an equal spread and needs plenty of room to fulfill its potential. The fragrant white flowers are said to be the purest white of all the magnolia flowers with red stamens, blooming in spring and continuing to bloom intermittently through the summer. The flowers are followed by prominent pink oval fruits (to 3 inches long) that split open in fall to reveal orange to red seeds. Dark green leaves (3 to 6 inches long) turn golden yellow in fall. The Oyama Magnolia is best grown in moist, fertile, slightly acidic, organically rich, well-drained loams in partial shade. It will not tolerate poor soils or full sun in hot, summer climates. The branches can be brittle, so protect the plant from strong winds and cold winter temperatures.Site the tree in protected areas with morning sun with consistent moisture. Diseases, Insect Pests, and Other Plant Problems: No known diseases or insect pests. Spring flowers can be affected by a last frost. More information on Magnolia .

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 55 attributes.

How it fits the guild

Guild layer 2 - Understory (15-40 ft) Optimal soil pH Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Full plant profile

Growing Conditions
Plant type
Perennial; Shrub; Tree
Life cycle
Woody
USDA zones
5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
Light
Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
Clay; Loam (Silt); Sand
Soil pH
Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Moist
NC region
Mountains; Piedmont
Mature size
Height: 13 ft. 0 in. - 26 ft. 0 in. | Width: 13 ft. 0 in. - 26 ft. 0 in.
Growth rate
Slow
Maintenance
Medium
Canopy layer
2 - Understory (15-40 ft)
Form & Appearance
Habit / form
Multi-stemmed; Rounded; Spreading; Vase
Texture
Medium
Foliage
Deciduous
Leaf color
Green
Leaf shape
Elliptical; Oblong; Obovate
Leaf margin
Entire
Leaf feel
Leathery
Leaf size
3-6 inches long, 1-3 inches wide
Hairs present
Yes
Leaf detail
Leaf blade obovate, 3.5 to 6 inches long and 1.5 to 3.5 inches wide. Lower surface glaucous, usually with long, silky white hairs along major veins. The upper surface has curved hairs on major veins.
Fall color
Gold/Yellow
Flower color
Gold/Yellow; Pink; White
Flower value
Fragrant
Flower form
Solitary
Flower shape
Cup; Saucer
Flower size
3-6 inches
Flower detail
Flowers bloom in late spring, cup-shaped at first but saucer-shaped later, 3 inches across, erect to slightly nodding, and fragrant.
Bloom time
Summer
Fruit color
Red/Burgundy
Fruit value
Showy
Fruit size
1-3 inches long
Fruit detail
Fruit is red when mature, 2 1/2 inches long.
Stem color
Brown/Copper; Gray/Silver
Stem detail
Twigs are pale greyish brown, slender, with appressed grey hairs when young.
Wildlife & Ecology
Native status
Non-native
Origin
Central China to Japan and Korea
Food & Medicine
Harvest time
Fall
Landscape Use
Landscape location
Lawn; Woodland
Landscape theme
Asian Garden
Design feature
Flowering Tree; Specimen; Understory Tree
Garden tags
#deciduous #flowering tree #small tree #flowering shrub #shrub #fragrant flowers #partial shade #showy flowers #showy fruits #hairy stems #spring flowers #hairy leaves
Problems & Resistance
Insect problems
Magnolia Scale; Yellow Poplar Weevil
Disease problems
Sooty Molds
Propagation
Seed; Stem Cutting

Planted at Hunnicutt

Nobody’s planted this one yet.