November / 2006
At Home in the Garden

Unusual ginkgo tree
by:  

One of my favorite times to take long walks is in early November, when most of the leaves have fallen and lay scattered all over the ground. Near my home there are several cemeteries that are great for exploring in the fall. I like to head out early in the morning, so I can see all the leaves as they have naturally fallen from the night before and remain untouched by passing cars or people.

If you are in Louisville and have a little free time for a garden walk, I recommend hiking through Cave Hill Cemetery. A true garden cemetery, they have an impressive collection of plant material, and fortunately a large portion of it has identification labels. One of the best places to start is at the office, which is located next to a large lake where you can feed the ducks before you set out.

Ginkgo tree characteristics
One tree you will see throughout your walk in Cave Hill is the ginkgo or maidenhair-tree—Ginkgo biloba (not to be confused with the herb ginkgo).

The unique shape of the ginkgo leaf makes it very identifiable. Its image can be found on everything. In my own house I can think of several pieces of jewelry, a vase, and a decorative plate that represent the simple fan-shaped ginkgo leaf.

In the summer, the leaf has a good unique, bright green color. In the fall, it has the absolute best yellow fall color you can find. The yellow is solid and not clouded with brown or green like many other leaves in the fall.

It seems there is nothing about the ginkgo that isn’t unusual or unique. Its shape, or habit, is strong and sculptural in the winter and softer in the summer. I am certain that I have never seen any two that looked anything alike. Vigorous when young and slow growing as it matures, the ginkgo can grow 50 to 80 feet tall but it can take 50 to 100 years to get there. This tall and equally wide plant is too big for many small urban gardens or as a street planting. It is best reserved for large gardens, farms, and parks where it can grow freely.

Avoid female ginkgos
Unlike most trees, ginkgo trees are either male or female. Male cultivars are commonly found for purchase in garden centers but the females are not. We do not recommend planting a ginkgo of unknown origin because the fruit of the female ginkgo stinks…and that is being nice. The small 1- to 1-1/2-inches long oval fruits of the female tree begin to ripen in early fall, and as they fall to the ground and get smashed or rot naturally, the smell can be almost unbearable. They are said to not produce fruit until a mature 20 to 30 years old, but I have seen fruit on much younger plants.

Common ginkgo cultivars
The most commonly available male cultivars are Autumn Gold, considered the best of the current cultivated male varieties; Shangri-la, a slightly more compact growing form; and Princeton Sentry, the most upright growing. All the cultivated varieties have to be vegetatively propagated, so that what you propagate from, that’s what you get. So don’t let the thought of the yucky smelling fruit stop you from planting a ginkgo tree. Just be sure to visit a great garden center and purchase a known male variety. Then you can plant and enjoy a tree that has been enjoyed and respected for hundreds of years.