Gardening for Health

Meet the State Flower

By Maria Price

In 1918, the state of Maryland adopted the black-eyed Susan as its official state flower. Their bright yellow faces bloom from July to August and through September, and maybe even longer depending on the weather. 

There are approximately 15 species that have been described and all are native to this country. They appear from the eastern seaboard to the prairie states but perhaps fewer than six species are known by gardeners, only a few are known very well.

The wonderful old-fashioned black-eyed Susan (Rudbeckia hirta) has been bred so much, it is scarcely recognizable now. The extremely popular Rudbeckia fulgida var. ‘Goldsturm’, was discovered by Germans, and brightens the day wherever it is planted. It grows 1½ to 2 feet tall. It is an excellent long-lasting summer daisy, outstanding in any full sun, well-drained area. Its native habitat is woodlands and meadows from New Jersey to Missouri, south to Mississippi, and east to Florida. It is hardy in USDA Zones 3 to 8.

The plants usually need cutting back hard once flowering has finished. They make so many flowers that when they begin to disintegrate in late summer and fall, they turn brown and are prime for fungal infestation. Clean up plants by removing dead foliage in the fall.

Rudbeckia hirta, the more common black-eyed Susan variety, grows 1 to 3 feet tall and bears rough, hairy alternate leaves, which may be divided, cleft, lobed, or entire. The flowers are yellow to orange with a black cone. Unfortunately, these annual and biennial plants are susceptible to many foliar diseases, especially botrytis, the fungal disease that turns the leaves black; this is a major problem when plants are crowded, or when a combination of humidity and rain occurs.

They all overwinter as basal rosettes, flowering from late spring into late summer. Seeds are readily available. Some of my favorite varieties are “Becky”, “Cherokee Sunset”, “Gloriosa”, “Goldilocks”, “Green Eyes”, “Indian Summer”, “Marmalade” and “Prairie Sun”. It is hardy in Zones 9 to 11 and prefers full sun and moderate moisture. It often reseeds itself.

Rudbeckia hirta is the larval host plant to the wavy-lined emerald moth, the southern emerald moth and the silvery checkerspot butterfly. Longhorn bees, leafcutting bees, cuckoo bees, bumblebees, sweat bees, and green carpenter bees all love the pollen and nectar of these black-eyed Susans.