Aconitifolium Full Moon Japanese Maple

Fernleaf fullmoon maple (*Acer japonicum* ‘Aconitifolium’) is a slow-growing, deciduous small tree or multistemmed shrub with a rounded, spreading outline and deeply cut, almost fernlike leaves. Its spring flowers are modest, but the green canopy and crimson, orange, or red fall color make it a distinctive specimen for cool, sheltered gardens. ## Form and seasonal interest The leaves are broad and palmately lobed, with narrow cuts that reach nearly to the petiole; they are not true fern fronds. Small reddish flowers appear before the leaves in spring, followed by paired winged samaras that mature in late summer or early fall. The foliage is medium green in summer and can turn crimson, orange, or red in autumn. North Carolina State Extension and Oregon State University describe a typical height of about **8–10 feet**. The Kwantlen Polytechnic University database lists a larger **3–5 m tall by 5–7 m wide** range, so allow extra lateral space where the plant grows vigorously. ## Landscape placement and growing conditions Use it as a specimen, in a small group beneath taller trees, at a woodland margin, or in a large container. The finely divided foliage and rounded outline work well where a small deciduous tree can be viewed close up. Give it full sun to part shade, with protection from harsh summer sun and drying winds. It grows best in cool-summer conditions and may struggle in hotter southern climates. Provide average, well-drained soil with moderate, even moisture; North Carolina State reports sandy, clay, or loam textures and neutral pH. Its documented hardiness range is **USDA Zones 5–7**. ## Cultivar identity The name *Aconitifolium* refers to leaves resembling monkshood (*Aconitum*). Oregon State lists *Maiku jaku* as a synonym and reports an RHS Award of Garden Merit in 1984. The institutional profiles reviewed identify this as an established named cultivar but do not name a breeder, branded series, or plant patent number. ## Sources [North Carolina State Extension](https://plants.ces.ncsu.edu/plants/acer-japonicum-aconitifolium/), [Oregon State University Landscape Plants](https://landscapeplants.oregonstate.edu/plants/acer-japonicum-aconitifolium), and [Kwantlen Polytechnic University School of Horticulture](https://plantdatabase.kpu.ca/PlantPrint/acja). ## Maintenance Care is modest once established. Water deeply during extended dry spells, especially while young, and keep the root zone evenly moist without waterlogging. Mulch over the root area while keeping mulch away from the trunk. Prune selectively in dormancy to remove damaged or crossing branches; stake a young tree only if a more upright trunk is desired. Choose a sheltered site and protect its early spring growth from late frost. Serious pest or disease problems are not usual, though occasional maple insects, leaf spots, or rots can occur.