Propagation
Seeds require moist stratification at 20º C (68°) to 30º C (86°F) for 28 to 60 days, followed by 80 to 90 days at 5º C (41°F). Fresh green seeds have a higher germination rate than the hardened dry seeds and the green seeds will germinate the following spring.
Cuttings taken from mid to late spring up to 200 mm (8 in) long and a place in a media composed of perlite and peat moss. After roots appear the cuttings require a dormancy period until spring when they should be potted up.
Cuttings can be difficult and unreliable and cultivars are normally grafted onto seedling stock.
Botanic information
Leaf: The ovate leaves are up to 20 mm (µ in)with an acute to obtuse apex and a rounded base with a petiole up to 12 mm (½ in) long. The margins are biserrate and the glabrous upper surface has a slightly raised reticulate veins. During autumn the leaves turn red, orange and yellow before falling and are a feature of the plant.
Flower: The ascending female (Pistillate) flowers have perianth segments that are adnate to the ovary with 6-10 teeth along the top and a short style with a linear stigma. They are arranged in catkins up to 76mm (3 in) long and the yellowish male (staminate) naked flowers have 3-15 stamens and arranged in a pendant catkin up to 65mm (2½ in) long and appears during spring.
Fruit: The upright fruiting catkin is up to 76mm (3 in)long and contains small achene-like nuts that are enclosed in a 3-lobed, papery bract. They appear in pendant clusters and fall from the tree during autumn. They are very viable but the plant may be reproduced vegetatively.