This common goldenrod is at home in the native plant garden at the Atlanta Botanical Garden.
Sweet goldenrod is a perennial with 2-5 ft (0.6-1.5 m) stems arising from short rhizomes. The hairy stems bear alternate stemless single-veined narrow dark green leaves with smooth or hairy margins and pointed tips. The leaves are 1-4 in (2.5-10.2 cm) long and smell like licorice when crushed. In late summer, densely crowded golden-yellow flowers appear in branched clusters at the tops of the stems. The individual blossoms are arranged in rows along the upper sides of the flower head branchlets. Fuzzy pale gray seedheads containing tiny nutlets replace the blossoms later in the season. S. odora var. chapmanii is recognized as a separate botanical variety from S. odora var. odora. (The hairs on the stems of var. chapmanii are fairly evenly distributed, though perhaps a bit sparse in a strip below each leaf base, whereas the hairs on var. odora stems are in distinct vertical lines.) Goldenrods tend to hybridize, so identifying them to species, much less variety, may be challenging.
Sweet goldenrod is native to the eastern United States, from Nova Scotia south to Florida and west to Arkansas and Texas. It occurs in sandhills, open xeric hammocks, and similar thin dry woodlands, as well as on oldfields and disturbed sites. This species rapidly grows back in increased abundance after fire or site disturbance, so it often makes a showy display on a newly cleared site.
Sweet goldenrod naturally occurs on poor sandy soil, but will do better on a reasonably fertile site. It performs well on heavy clay.
Light: Sweet goldenrod will grow in full sun or semi-shade. Moisture: Although this species grows on very dry sites in the wild, it appreciates garden irrigation. Hardiness: USDA Zones 5 - 9. Propagation: Either scatter newly ripened seeds directly onto tilled or raked ground where they are to grow or save them and start them in the spring in a coldframe. Germination may be unreliable, so sow thickly. Barely cover the seeds and keep the planting medium moist. Prick out the seedlings and pot them up individually as soon as they are sturdy enough to handle. Keep them in pots through their first winter, then set them out in late spring or summer. Clumps may be divided in spring or fall. Large divisions can go straight into the garden, but small plants are delicate and should be nurtured in pots until they are well developed, then set out in early summer. Be careful not to plant them more deeply than they originally grew or the stems may rot.
Pollen from the showy goldenrod flowers is not a cause of hayfever.
Sweet goldenrod is often grown in wildflower gardens, meadows, and naturalistic borders. The leaves make a flavorful herbal tea. Due to its strong anise flavor, there has been interest in using oil extracted from this species as a flavoring agent. Sweet goldenrod leaves and tops (picked during the flowering period) have been used to make herbal medicines for a variety of disorders, including digestive and urinary problems, wounds, ulcers, and cancers. Prior to the advent of effective anesthesia, seeds of this species were used to promote a delirious and forgetful state of mind in surgical patients. The flowers yield a deep yellow dye.
Sweet goldenrod is a great plant to grow alongside a sandy trail or driveway. Ample plants for a colorful show will spring up if seeds are generously scattered into the loose soil. The flowers will attract ladybugs, lacewings, hoverflies, and other garden-friendly insects.
This is a greedy plant that will draw more than its share of nutrients from the soil and compete aggressively with neighboring plantings. Goldenrod pollen is too heavy to drift through the air in great clouds and cause the widespread hayfever problems it was once falsely accused of, but it may make you sneeze if you sniff the blossoms. Goldenrods have also been linked to cases of allergic dermatitis and the leaves appear to be toxic to sheep. Although sweet goldenrod tea is apparently a wholesome beverage, a toxic fungus that sometimes grows on the leaves may poison tea made from infected leaves.