Acer pseudosieboldianum Seeds | Korean Maple
LATIN NAME: Acer pseudosieboldianum
COMMON NAME: Korean Maple
Plant Profile
Korean maple is a small deciduous tree of the mountains of Korea, northeastern China and eastern Russia, where it grows as an understorey species in mixed forest. It reaches six to eight metres, with nine- to eleven-lobed, palmate leaves that are broader and more rounded than those of the Japanese maple.
The autumn colour runs from yellow through orange to deep scarlet, and it holds for several weeks. The flowers are small and purplish, opening with the leaves, and the winged seeds ripen in autumn and spin as they fall. The bark is smooth and green on young stems, turning grey and slightly rough with age.
Science & Biotechnology
The species is important in maple breeding because it is markedly hardier than the Japanese maples, surviving -30C and the late frosts that damage its relatives. Hybrids with Acer palmatum, raised in North America, combine the hardiness of the Korean parent with the finer foliage of the Japanese one, and they are now sold as a group in their own right.
Studies of its leaf anatomy have looked at how the species avoids frost damage in spring, and its wood anatomy has been compared with that of other Asian maples. In Korea it is included in surveys of understorey diversity in mixed mountain forest.
Uses & Benefits
In cold gardens it is the best substitute for a Japanese maple, giving the same layered habit and autumn colour without winter protection. It works as a specimen in a lawn, in a raised bed or in a large container, and it can be trained as a small multi-stemmed tree.
In its native range the wood is used for small turnery and tool handles, and the young leaves are sometimes gathered as a spring vegetable. Its main value outside Asia is ornamental, and it is one of the few maples that will colour reliably in a short, cool growing season.
In Korea the tree is planted in gardens and temple grounds, and its leaves are used in some regional dishes, wrapped around rice in the way that other large leaves are. Its tolerance of cold has also made it a rootstock candidate for less hardy maples in northern nurseries.
Growing from Seed
Sow in autumn and leave the pots outside for winter, or stratify for twelve weeks; germination is often in the second spring. Plant out in light shade with shelter from strong wind, in moist, well-drained, slightly acidic soil.
Mulch with leaf mould, and do not prune hard, since the tree bleeds and heals slowly; remove only dead or crossing wood in late winter. Protect young plants from late frost, which can blacken the new leaves. In a container, use a lime-free compost and keep the root out of direct sun, since the shallow roots scorch easily.
Our Take
For a cold garden this is the maple to grow: hardier than the Japanese species, just as colourful in autumn, and easier to place in a small space.
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