Kentucky coffee tree (Gymnocladus dioicus) sounds like it needs a barista instead of a gardener to tend to it. Part of its name is an accurate designation -- formerly, it was Kentucky's state tree -- but it does not bear coffee beans. It was named by early American settlers who learned from Native Americans how to grind the seeds and brew a coffeelike beverage. But the merits of this tree go beyond its descriptive name.
Kentucky coffee tree is bare during half the year because of its leafless branches. It is one of the last trees to leaf out each spring, and one of the first to drop its leaves in autumn, which creates a window of only about six months during which it has leaves. The leaves are long -- up to 3 feet -- and composed of individual leaflets. New spring growth emerges as pinkish-bronze before turning to blue-green in summer and yellow in the fall. The twigs are greenish-brown with white patches and new branches form zigzag patterns.
Fragrant Flowers and Messy Seedpods
A Kentucky coffee tree is either male or female. Both sexes produce greenish-white flowers in spring. The female tree bears fragrant blossoms in panicles that may reach 12 inches, and male trees produce flower clusters that typically are 4 inches long. Only the female trees bear seeds, and only if the flowers are fertilized by a male tree. The seeds are contained in flat, reddish-brown seedpods that may be up to 10 inches long, maturing in October but remaining on the trees until late winter or early spring. The female trees are messy when they release the seedpods, which litter the ground.
A deciduous perennial in U.S. Department of Agriculture plant hardiness zones 3 through 8, Kentucky coffee tree typically is a low-maintenance plant that tolerates air pollution. It needs room to spread out because mature trees may reach 80 feet tall and 50 feet wide, but its roots won't cause problems. Although it prefers rich, moist soil, and is a suitable plant for rain gardens, the tree can also tolerate drought. If you need to shape Kentucky coffee tree to keep it tidy, prune it in winter or early spring. Disinfect your pruning tools by mixing a solution of 1 part household pine-oil cleaner and 3 parts water. Soak the pruners for five minutes and rinse them thoroughly before using.
The Good With the Bad
Although female trees drop many seedpods, Kentucky coffee tree does not spread invasively. The seeds have a tough outer coat, which makes germination difficult, and because squirrels are not fond of them, they do not scatter them about the landscape. Because the seedpods stay on trees throughout the winter, they look attractive and gently rattle in the breeze. The trees don't have problems with pests and diseases, and they tolerate a variety of soil types, except heavy clay. The seeds, leaves and new growth are highly toxic and may poison people and pets.
- Missouri Botanical Garden: Gymnocladus Dioica
- United States Department of Agriculture Natural Resources Conservation Service: Kentucky Coffeetree
- University of Kentucky Cooperative Extension Service: Champion Trees in Fayette County -- Kentucky Coffeetree
- University of Florida IFAS Extension: Gymnocladus Dioicus -- Kentucky Coffeetree
- University of Florida IFAS Extension: Disinfecting Pruning Tools
- Photo Credit fisfra/iStock/Getty Images
Kentucky Tree Leaf Identification
Located on the western slopes of the Appalachian Mountains along the Ohio River, Kentucky has a rich and varied flora, which includes...
How to Identify a Tree With a Sticky Seed Pod
Some species of tree have sticky seed pods. You can learn to identify the trees that produce your sticky seed pods by...