Varnish Tree Koelreuteria paniculata

The golden rain tree is a medium-sized deciduous tree in the maple family (Sapindaceae) family. It is a great urban flowering tree that tolerates drought, heat, wind, and air pollution and grows 30 to 40 feet tall high and equally as wide. It has spreading branches but a rounded crown. This tree has a medium to fast growth rate and transplants and self-seeds easily.

It flowers at an early age with a display of summer yellow flowers that produce a fireworks show of bright color.  When the blooms are finished and the petals drop to the ground resembling a "Golden Rain" blanket, hence the common name. The yellow color is echoed in the feathery compound leaves come fall, but it is inconsistent, so not particularly showy. The fruit display is very distinctive with three-parted dry tan capsules, and these showy fruits are sometimes used in dried arrangements.

The golden rain tree is native to China, Japan, Korea, and Manchuria. It was first introduced to North America in 1763. It is currently on the National Park Service, Mid-Atlantic Exotic Plant Management Team Invasive Plant List.

The genus name, Koelreuteria, is in honor of Joseph Gottlieb Koelreuter who was a German professor of botany and experimented with plant hybridization in the 18th century. The specific epithet, paniculata, refers to the tree's panicle-like floral inflorescence.

Plant this soil-adaptable tree in full sun. While it tolerates a range of soil types it prefers moist, well-drained, and acidic to alkaline soils. It is tolerant to drought and urban air pollution. This tree is mildly resistant to damage by deer.

Golden rain tree works well planted on a lawn or park or near a patio, though consider the flower and leaf litter if planted near any hardscape. Use it to shade children's gardens where the flowers and fruits can be enjoyed. It may also be used as a shade tree or street tree.  This tree can escape cultivation and naturalizes in various conditions. You may wish to consider a native plant alternative.

Seasons of Interest:

Bark;  Winter   Bloom: Summer    Foliage:  Summer and Fall          Fruits:  Summer, Fall, and Winter

Quick ID Hints:

• 12 to 15-inch long panicles of yellow star-shaped flowers that bloom in mid-summer.
• Sparsely branched small tree rounded form
• Fruits are dehiscent, papery, and 3-valved
• Stems also have prominent, shield-shaped leaf scars. Prominent hairy buds and twigs have orange-brown lenticels
• Leaves are pinnately compound, 6 to 18-inches long, and have 7-15 leaflets
• Leaflets near the leaf base are deeply lobed

Insects, Diseases, and Other Plant Problems:  The golden rain tree has no serious insect or disease problems.  It may sometimes suffer from coral spot fungus, root rot, and cankers. Verticillium wilt may cause wilting of the leaves and can eventually kill the tree.  Occasionally scales may be seen, and the boxelder bug can be problematic.  It reseeds easily and can become weedy. It tends to have brittle wood so can be damaged in storms or during the winter.

VIDEO created by Grant L. Thompson for “Trees, Shrubs, and Woody Vines for Landscaping” a plant identification course offered by the Department of Horticulture at Iowa State University.