How to Grow and Care for Kentucky Coffee Tree

The native Kentucky coffee tree (also known as Kentucky coffeetree), is a tall and picturesque ornamental shade tree with enormous leaves, sometimes up to 3 feet long and 2 feet wide that emerge as pinkish-bronze, then turn blue-green. The majestic Kentucky coffee tree grows best in large open areas with full sun. It's adaptable to a wide range of soil conditions, and it thrives in all types of temperatures and humidity levels, except extreme heat. The leaves, fruit, and seeds of this tree are toxic to humans and animals.

Common Name	Kentucky coffee tree
Botanical Name	Gymnocladus dioicus
Family	Fabaceae
Plant Type	Perennial deciduous tree
Mature Size	65-75 ft. tall, 40-50 ft. spread
Sun Exposure	Full
Soil Type	Loamy, moist, well-draining
Soil pH	Acidic, alkaline, neutral
Bloom Time	Spring
Flower Color	Green, white
Hardiness Zones	3-8 (USDA)
Native Areas	North America
Toxicity	Toxic to humans, toxic to pets

Kentucky Coffee Tree Care

Here are the main care requirements for growing a Kentucky coffee tree.

• Plant the tree in full sun.
• Provide sandy loam soil but the tree will tolerate clay.
• Do not overwater this drought-tolerant tree.
• Do not fertilize with a nitrogen product since this tree fixes nitrogen in the soil.
• Prune weak branches of maturing trees; leave young trees unpruned.
  

Light

The Kentucky coffee tree does best with at least six to eight hours of direct sunlight. The tree will tolerate a small bit of shade.

Soil

Adaptable to a wide range of soil conditions, this tree manages well in clay but grows a bit better in sandy loam. It isn't bothered by too much acidity or alkalinity. Being drought-tolerant, it's also fine in dry spots. Too much wet soil may affect the roots over time, so planting too near a swamp or marshy spot is not a good idea.

Water

In times of extended drought, this tree will benefit from some additional watering at its base, about every seven to 10 days. But otherwise, it's very drought-tolerant and should not require extra water.

Temperature and Humidity

Kentucky coffee tree isn't too fussy about temperature or humidity and is very winter-hardy. It's not likely to do well in growing zones higher than 8. It struggles in hot, dry climates.

Fertilizer

Fertilize the Kentucky coffee tree with fertilizing products that promote woody, strong growth rather than excessive foliage growth. Avoid fertilizing with nitrogen products, since the tree is a nitrogen fixer. (It even works to supply neighboring plants with nitrogen.)

Types of Kentucky Coffee Tree

There are several cultivars available through the nursery trade, most of them male, which do not produce fruit or showy flowers. They produce less pod litter, making them more suitable for smaller urban settings such as streets and smaller yards.

• 'Espresso': This grafted seedless variety is one of the most popular male cultivars available. The arching branches form a vase shape and the compound leaves make it a desirable shade tree.
• 'Prairie Titan': This is another male fruitless cultivar with an upright spreading shape. The foliage tends to be more bluish-green than other cultivars.
• 'Stately Manor': This male cultivar has a more narrow upright form, but the spread may still reach up to 50 feet wide at maturity.

Pruning

The best time for pruning the Kentucky coffee tree is late winter or early spring after the worst cold temperatures are no longer a danger. Its slow growth habit means that young trees won't need any pruning in the first few years unless the branches become damaged. However, if overly long (thereby weaker) branches develop, these should be pruned when young to promote a stronger structure.

How to Grow Kentucky Coffee Tree From Seed

Most growers of the Kentucky coffee tree prefer the easier method of propagating this plant by seed. It's easy to grow a Kentucky coffee tree from seed if you can harvest the pods and release the seeds. Harvest them after the pods have turned brown in late winter to early spring. For successful germination, seeds need to be scarified (but not stratified) to remove the layers of protective coatings. Take these steps:

1. Peel the large seeds out of the pods and remove the protective sticky, jelly-like outer coating.
2. Scarify the seed coat by removing the extra protective brown-black waxy coating with a small file. Keep filing until you can see the true seed, which is more yellowish.
3. Soak the seeds in boiling water (hot is okay) and let the water get to room temperature when soaking for 24 hours. Peel off the waxy coating after seeds soak.
4. Put the seeds an inch or two down into a small pot of potting soil like you would any other seed.
5. Keep in a warm, humid, indirectly lit space, such as a greenhouse.
6. In a few months, the seedling should reach about 6 inches tall with sets of true leaves. Transfer the tree outdoors in the spring when the soil is consistently warm. (You can wait up until three seasons before planting the tree outdoors if you desire.)
   

How to Get Kentucky Coffee Tree to Bloom

Bloom Months

The pale green panicles begin to emerge on female trees in late spring to early summer (late May to early June).

What Do Kentucky Coffee Tree Flowers Look and Smell Like?

The female trees bear showy 12-inch long panicle clusters of pale greenish-white star-shaped flowers. The flowers have a fragrance similar to roses.Note that male trees do flower, but they are insignificant and easy to miss, and they are not grown for their blooms. If buying a Kentucky coffee tree seedling or this tree's seeds from a nursery, be sure to find out the gender you are purchasing.

How to Encourage More Blooms

The flowering female tree needs six to eight hours of unfiltered sun daily for the best blooms.

Common Problems With Kentucky Coffee Tree

This tree has no real disease or insect problems to worry about. There are only a few issues that may be of concern.

Leaf Litter

"Leaf litter" from both male and female trees can be a problem as the leaves are very large and most of them come off the branches in the early fall. The fallen seed pods from female trees, beginning in the spring, can also create a bit of a mess. This makes the tree a better candidate for parks or other open areas, such as a very large backyard, rather than as a street tree.

Contorted Branches

After the leaves fall, the tree's large, twigless, and completely naked branches will have a contorted zig-zag pattern. This silhouette gives this tree a bold fall and winter appearance perfect for a "haunted Halloween" setting that some gardeners may or may not appreciate.

Yellowing Leaves

This tree does not like to be overwatered, and as a result, it may show yellowing leaves that wilt and drop off too early. The tree usually tolerates occasional flooding conditions.

No Leaves

Kentucky coffee trees are one of the last trees to leaf out in the spring and the earliest to drop leaves in the fall. The trees are leafless most of the year, so it is not unusual to have bare branches from fall through much of the spring.

From: thespruce