Alnus japonica is usually a small to medium-sized tree, but can grow into a large tree of 20 m or even higher under favourable conditions. The crown is initially relatively narrowly upright, but later widens to form a conical crown. The leaves are a glossy dark green, sometimes the young shoots are bronze coloured. The leaf margins are shallowly serrated. The male and female catkins mature in late winter. They are followed by the characteristic alder cones. These are green at first but turn dark brown as they ripen. Naturally, A. japonica often grows along stream and river banks or in swamps. The tree grows in any soil type, but the soil should be sufficiently moist or even wet. Despite being introduced to the Netherlands as early as 1866, it has never been a common species. Nevertheless, the fact that this elegant little tree is suitable for use on moist to wet soils offers plenty of opportunities for planting along banks and in wadis.
Alnus japonica môže dorastať do výšky 15-20 m v závislosti od podmienok stanovišťa a klímy.
Alnus japonica rastie priemerne rastúci a môže dorastať do výšky 15-20 m v závislosti od podmienok stanovišťa a klímy.
Správny čas na výsadbu stromu je mimo vegetačné obdobie. V strednej Európe môže byť Alnus japonica so zemným balom vysadený od polovice novembra do konca apríla, avšak závisí to veľmi od klimatických podmienok a druhu stromu.