Japanese Maple ‘Senkaki’ · Acer palmatum ‘Senkaki’

'Senkaki' (synonym 'Sango-kaku', Japanese for coral) is distinguished from the species and from the red-leaved palmatum cultivars by a trait uncommon in the genus: coral-red to coral-pink current-year shoots and young branchwork that intensify under winter cold and carry the visual interest from leaf-fall to spring break. The cultivar's specification case rests on this winter feature; positioning it as a generic arce japonés misses the only reason to choose it over the more drought-tolerant red-leaved selections that Spanish viveros routinely hold.

Foliage palmate with five to seven lobes, not dissected, pale to yellow-green through summer, with autumn colour in butter yellow and apricot orange between mid-October and early November in cool maritime conditions. Habit upright vase in youth, broadening with age to about 4 to 6 m in height and 4 to 5 m in crown spread at twenty years, with a finer and more regular branching pattern than the type. Growth slow, of the order of 20 to 30 cm per year in favourable conditions.

Site requirements are strict. Fresh, well-drained, slightly acid soil with organic matter; intolerant of the calcareous heavy soils characteristic of much of the central and southern peninsula, and of seasonal waterlogging. Drought tolerance is low and the cultivar requires summer irrigation in every Spanish climate zone, including the established phase. Full sun in the meseta continental interior, the valle del Ebro or the sureste árido scorches young foliage; reserve for cool half-shade with afternoon protection.

The coral bark intensity depends on a real winter cold differential. The cultivar performs at full display in the cornisa cantábrica, the Empordà foothills, the cooler interior of the Maresme and the mid-altitude of the Sierra de Guadarrama below about 1,300 m. On the Costa del Sol, the Costa Blanca and the Balearic coastal strip, the mild winters mute the colour, and the cultivar functions principally for autumn colour and habit. Xylella fastidiosa host-range status: Acer is not currently listed among the priority Spanish host genera, and the species is not under specific phytosanitary alert. Cold hardiness to about -15 °C in sheltered positions.

Use as a contemplative specimen against a dark evergreen backdrop or pale wall that supports the bark reading through the leaf-off months. Pruning limited to sanitary cuts after the third year.