Emperor I® Japanese Maple Tree

Emperor I® is the trade name for the Japanese maple cultivar ‘Wolff’, an upright, rounded small tree with dark red-purple foliage. It leafs out later than many Japanese maples, which can reduce exposure of tender new leaves to late spring frost. ## Landscape use and seasonal interest Use it as a colorful specimen in a smaller landscape or courtyard where its crown has room to develop. [Monrovia](https://www.monrovia.com/emperor-i-japanese-maple.html) lists about 15 ft in height and width; [J. Frank Schmidt](https://jfschmidt.com/wp-content/uploads/2023/02/emperorijapanesemaple.pdf) lists 18 ft tall by 16 ft wide. RHS describes trees reaching about 5 m tall. Deep red-purple foliage turns crimson or scarlet in autumn; spring flowers are inconspicuous. See the [RHS profile](https://www.rhs.org.uk/plants/160503/acer-palmatum-wolff/details). ## Siting and growing conditions Grow in full sun to partial shade. Monrovia recommends slightly acidic, well-drained soil and shelter from drying winds. Mulch can help keep roots cool. Water regularly through the first few growing seasons, then reduce frequency as the tree establishes. ## Maintenance Prune only as needed, preferably during dormancy, to remove damaged or crossing branches and maintain a balanced crown. Keep soil moisture adequate during establishment and hot, dry weather.