[6] Many different cultivars of this maple have been selected and they are grown worldwide for their large variety of attractive forms, leaf shapes, and spectacular colors.
[9][10] Even in nature, Acer palmatum displays considerable genetic variation, with seedlings from the same parent tree typically showing differences in such traits as leaf size, shape, and color.
When Swedish doctor-botanist Carl Peter Thunberg traveled in Japan late in the eighteenth century, he produced drawings of a small tree that would eventually become synonymous with the high art of oriental gardens.
Japanese horticulturalists have long developed cultivars from maples found in Japan and nearby Korea and China.
Numerous cultivars are popular in Europe and North America, with red-leafed favored, followed by cascading green shrubs with deeply dissected leaves.
[9] Acer palmatum includes thousands of named cultivars with a variety of forms, colors, leaf types, sizes, and preferred growing conditions.
Trees naturally self-prune foliage that doesn't receive enough light, such as internal branches which are overly shaded by its own canopy.
[9] Cultivars are chosen for phenotypical aspects such as leaf shape and size (shallowly to deeply lobed, some also palmately compound), leaf color (ranging from chartreuse through dark green or from orange to red, to dark purple, others variegated with various patterns of white and pink), bark texture and color, and growth pattern.
Cultivars come in a large variety of forms including upright, broom, vase, umbrella, weeping, cascading, dwarf, shrub, and ground cover.
Most cultivars are artificially selected from seedlings of open-pollinated plants, purposeful breeding is not common, and less often from grafts of witch's brooms.
In Japan, iromomiji is used as an accent tree in Japanese gardens, providing gentle shade next to the house in the summer and beautiful colors in autumn.