Description
Kentucky Coffeetree
- Hardiness: USDA Zone 3
- Size at Maturity: 60 – 80′ tall and 40 to 55′ wide
- Edible Seeds (when roasted), Flowering
- Separate Male and Female Trees
- Source: Seeds
Gymnocladus dioica
The Kentucky Coffeetree is a North American deciduous tree growing to 60 to 80 feet tall and spreading 40 to 55 feet. It produces showy, fragrant flowers and large compound leaves up to three feet long and two feet across. Leaves turn a bright yellow in the fall.
The genus Gymnocladus is a member of the Fabaceae (pea and bean) family and can fix nitrogen due to a symbiotic relationship that this plant family has with soil bacteria. Female plants produce a reddish-brown pod up to ten inches long. Seeds are toxic when consumed raw but edible after being roasted. Ground, the roasted seeds have been used by first-nations to create a coffee-like drink giving the tree its common name.
Megafauna, like mammoths, consumed the fruit, similar to how elephants consume acacia (a relative) in Africa. The plant’s leathery fruit is inaccessible for most animals, and the seeds are too heavy to be moved by the wind. Having lost its symbiotic partners, it’s likely that the range of Kentucky Coffeetree was once much more extensive.
Kentucky Coffeetree is tolerant of drought and air pollution, making it suitable for urban environments. The genus name Gymnocladus translates to “naked branch” and references the tree’s tendency to leaf out late and drop its leaves early. This habit makes members of this genus suitable to locations that desire summer shade but sunlight in the shoulder seasons.