Fothergilla—A Four Season Shrub to Consider for Your Garden

 "The fothergillas ask so little from gardeners yet give so much; all friends should exhibit this kind of relationship." – Michael A. Dirr, horticulturist and a professor of horticulture

Fothergilla, or witch alder, is a deciduous shrub that provides four seasons of interest in your garden. In early April, white, one to three-inch long, bottlebrush-like blooms appear on the tips of its stems. The flowers’ wonderful, honey-like fragrance is beloved by early pollinators and sadly, deer. The flowers fade after two to three weeks and are replaced by blue-green, leathery, oval leaves. This shrub really shines as the weather turns cold. The fall foliage color is stunning and differs due to weather conditions during the growing season. The frost-tolerant leaves can be golden yellow, bright orange, or red, depending upon the amount of sunlight or rainfall. Temperature may also affect the color display. Fothergilla does develop non-descript fruit: a brown capsule containing two black seeds that forcibly eject upon ripening in summer. In winter, the upright, fan-shaped stems provide an interesting shape to your garden.

There are only two species of fothergilla: large fothergilla (Fothergilla major) and dwarf fothergilla (F. gardenii). Both are native to the southeastern United States but grow well in Pennsylvania. The flowers and leaves of each are nearly identical, but these two species have significant cultural differences to consider before adding to the home landscape.

Dwarf fothergillas naturally grow in damp areas along the coastal plain from North Carolina to Florida. Their USDA hardiness zone is 5 through 9. They prefer sun to light shade and moist, well-drained, acidic soil. Depending on the cultivar, they grow anywhere from 3 to 6 feet tall and 2 to 6 feet wide.

Large fothergillas grow along ridges, riverbanks, and dry areas in the southern Appalachians, from North Carolina and Tennessee to Georgia and Alabama. Their USDA hardiness zone is 4 through 8. They prefer the sun to light shade and moist, well-drained, acidic soil. They grow from 4 to 15 feet tall and 6 to 12 feet wide, depending on the cultivar.

There are several cultivars available in the retail trade. The most commonly available is ‘Mt. Airy', a naturally occurring hybrid discovered by Dr. Michael Dirr at the Mount Airy Arboretum in Cincinnati, Ohio. ‘Mt. Airy' has dark blue-green foliage, consistent yellow-orange-red autumn color, and abundant flowers with an upright habit of 5 to 6 feet tall.

Fothergillas are slow-growing shrubs with a mounded appearance. With no serious insect or disease problems, they are long-lived. Once blooms have faded, deer and rabbits leave them alone. Use fothergillas as foundation plantings, in masses or along borders. The brilliant autumn color makes them a good native alternative to burning bush or spirea. They are difficult to propagate from seed, but soft wood cuttings root easily. Fothergilla plants may spread by root suckering. To control the spread, simply remove the suckers from the outer edges of the clump and prune to several central stems.