Submitted by James Newburn


If you are looking to add color to your fall landscape, consider planting an American sweetgum tree (Liguidambar styraciflua), which produces one of the best fall displays. Now is a great time to plant a tree or shrub, because over the winter the tree's energy will be directed into root growth and establishment.

American sweetgums have five-pointed star-shaped leaves that are a beautiful glossy green in the spring and summer. The tree can be a spectacular specimen for fall color as sweetgums are famous for displaying multiple colors all at once! Quite often brilliant canary yellow leaves appear next to dark burgundy purple ones, with every shade of red shown over the rest of the tree.

Sweetgums are a great southern tree. They prefer warmer temperatures, being cold hardy only as far north as zone 5. Sweetgums prefer soils that are rich and well drained, but they can tolerate a variety of growth habitats. In ideal conditions, sweetgums can easily reach heights of 60 to 75 feet. Their canopy is very pyramidal and attractive.

The name "sweetgum" is derived from the tree's sweet, gummy sap. Sweetgums also have a very distinctive fruit. In the summer they will begin to produce small prickly ball-shaped structures about an inch in diameter. These fruit will darken and harden throughout the season, in some cases into winter. They can be a maintenance issue because once they drop from the tree, they are very hard and cannot be mowed over.

'Rotundiloba' is a fruitless cultivar. It has a slightly more pyramidal shape, and the leaves are slightly rounded, or lobed, rather than sharply pointed like the original sweetgum. 'Rotundiloba' was introduced in 1983 and prefers a slightly warmer habitat, preferably zones 6-9.

Sweetgums, regardless of the cultivar, need lots of space for root development, so this is a great tree for a large lot.

Other trees that you might consider planting for fall color include maples, sassafras, and some of the oaks. Maple trees offer a wide variety of colors depending on the species. For example, sugar maples (Acer saccharum) usually turn a brilliant orange, while the silver maples (Acer saccharinum) usually turn yellow. Sassafras (Sassafras albidum) turn orangey-red, and some of the best oaks, red and pin (Quercus rubra and Quercus palustris respectively), turn brilliant red. Ginkgo (Ginkgo biloba) will turn a dazzling yellow and keep its colored leaves for a long time before dropping them all at once.

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James Newburn is curator of the University of Tennessee Gardens. He works with Gardens Director Dr. Susan Hamilton. The UT Gardens are located on Neyland Drive in Knoxville. Admission is free, and the Gardens are open to the public seven days a week during daylight hours.