Acer palmatum Royal Garnet

Acer palmatum Royal Garnet, known by its cultivar name 'Opstal11', is a Japanese maple with deeply incised foliage in a beautiful garnet colour. It forms a small, highly branched shrub with an initially upright and dense habit, then becoming rounded, wide and spreading from around 5 years. In autumn, the feathery and delicately carved foliage turns a fiery orange-red, with bluish highlights. This maple prefers moist to wet, well-drained soil and a location in non-scorching sun or partial shade. It is hardy down to -15º C.

Acer palmatum is native to eastern China, Korea, and Japan. Like all maples, it belongs to the Aceraceae family. Royal Garnet stands out for its carved foliage, coloured in purple-red to garnet red, from spring to summer. It is a fairly hardy, slow-growing small tree with brown wood, which develops a single trunk supporting an initially upright and then spreading, sparsely branched crown, supported by flexible branches. At 7 years old, it reaches 2 m in height and about 1 m to 1.5 m in width, depending on the growing conditions. Its deciduous foliage is composed of palmate leaves, measuring 5 to 8 cm long, deeply divided into 5 to 7 lanceolate lobes, finely carved and strongly toothed along the edges. The reddish flowers grouped in small clusters in April are insignificant, but the 3cm long red fruits with curved wings are interesting from September onwards. Before falling in autumn, the foliage takes on beautiful bright red and orange hues.

Acer palmatum Royal Garnet prefers acidic, moist, fertile, loose, and well-drained soil, in a partially shaded position sheltered from cold and dry winds. It tolerates non-scorching sun. High temperatures cause the leaves to burn and fall quickly. It is ideal as a standalone specimen on a lawn or in an ericaceous soil bed accompanied by azaleas, pieris, rhododendrons, and heathers. In a Zen garden, it pairs well with bamboos and Cornus kousa. It can also be trained into a beautiful bonsai in a flat tray.

Tips: Treat with Bordeaux mixture to prevent Verticillium attacks.