Shirasawa Maple

Shirasawa maple occupies the space between Japanese maple and fullmoon maple, and if you have a well-curated garden in the Puget Sound lowlands you may already be growing one without realizing it is a separate species. Native to the mountain forests of Honshu and Shikoku in Japan, it grows ten to thirty feet tall with rounded, almost circular leaves, smaller than fullmoon maple but rounder than Japanese maple, and a delicate, layered branching structure. The flowers are small and upright with white to pale yellow petals. Fall color is the main event: crimson, orange, red, and yellow in combinations that can vary from branch to branch on the same tree.

In Western Washington, Shirasawa maple fits the same design niche as Japanese maple but with a slightly different texture and color signature. It takes full sun to full shade, which is unusual flexibility for a tree with this level of ornamental refinement. The maritime climate suits it well, and it handles our wet winters without the root rot issues that plague some ornamental species. The standard maple genus susceptibility list applies, Verticillium wilt, anthracnose, powdery mildew, leaf blister, and the rest, but healthy specimens in well-drained sites rarely show serious problems. The practical challenge is availability: Shirasawa maple is less commonly stocked than Japanese maple, and you may need to visit a specialty nursery or order from a collector grower to find one.