Golden Raintree

Koelreuteria paniculata (Sapindaceae) is a deciduous tree native to China, Japan, and Korea. It grows slowly to 25 to 35 feet tall with a 32-foot spread, forming a rounded crown with spreading and ascending branches. The alternate, pinnately compound leaves emerge reddish-copper in spring, mature to bright green, and turn yellow in autumn. In June to July, large terminal panicles (30 to 40 cm) of small yellow four-petaled flowers create a striking display, followed by papery, lantern-like capsule fruits that persist through fall and winter.

Golden raintree is notably adaptable: it tolerates a pH range of 4.5 to 8.0, clay soils, drought, and urban air pollution. Full sun produces the best flowering. Bloom starts around 1,159 GDD (base 50 F) with full bloom near 1,424 GDD. The cultivar 'Fastigiata' offers a more upright form. No significant pest or disease problems are documented. The species has been considered invasive in some regions of the United States due to prolific self-seeding. It holds historical significance as one of the five official memorial trees of the Zhou dynasty in China. Hardy in Zones 5a to 8b.