Mums are a go-to for fall flowers, but they're often best considered annuals to replant each year. As an alternative, check out this handful of reliably perennial fall bloomers to plant once and enjoy for seasons to come. These are all part of the Mt. Cuba Collection, a group of plants selected and introduced by Mt. Cuba Center, a botanic garden in Delaware. The center, known for its extensive research on native plants and their performance in gardens, has introduced roughly 20 named perennials over the past few decades.
“With the collection, we’re taking a snapshot of the better older introductions that you can still get commercially, plus some newer standouts,” explains Sam Hoadley, who manages the Trial Garden at Mt. Cuba Center. These plants—all selected as chance seedlings or sports, not hybridized for certain traits—rose to the top in three-year trials that assess value to gardeners and beneficial insects.
The four fall-blooming members of the Mt. Cuba Collection are:
1. ‘Gold Standard’ tall tickseed
(Coreopsis tripteris ‘Gold Standard’)
“The species has a ton of merit,” says Sam, “but ‘Gold Standard’ makes it more accessible to home gardeners with less space.” Straight Coreopsis tripteris reaches seven feet tall or more and it was found to flop under its own weight in Mt. Cuba’s coreopsis trial. Meanwhile ‘Gold Standard’ tops out at five to six feet and remains upright. Sam points out “there’s no need to do a Chelsea chop” (late-spring cutting back) of the stems to promote its steadfast stance. Blooming from late summer into early fall, it feeds many pollinators and then delights American goldfinches with its seed.
Origins: Coreopsis tripteris is native to open woods and damp prairies of the Mid-Atlantic, Southeast and Central U.S. Introduced in 2016, ‘Gold Standard’ was selected out of plants grown from seed collected in Alabama.
Growing notes: Provide it with full sun and moderate moisture. Shallow roots make tall tickseed tolerant of rocky and clay soils. Like the species, ‘Gold Standard’ slowly spreads by rhizomes, or underground stems, but it is not aggressive. Zones 3–8.
2. ‘Bluebird’ smooth aster
(Symphyotrichum laeve var. laeve ‘Bluebird’
)
This was the top performer in Mt. Cuba’s 2003 to 2005 aster trial. It heralds fall with light purplish-blue ray flowers that support pollinators, including migrating monarch butterflies, in the late season.
“I grow this at home and (the flowers are) just covered with small insects,” says Sam. The blossoms are small, but they occur in great abundance on this dense, upright, three- to four-foot-tall plant. “You could chop it to make it more compact, but it’s not necessary,” he notes. Diseases can trouble aster foliage, but this one’s remains clean all season.
Origins: The species variety S. laeve var. laeve is native to open woods and dry prairies of much of eastern North America as well as parts of the Interior West. Cultivar ‘Bluebird’ originated as a chance seedling in a Connecticut garden in 1988. It was shared with Mt. Cuba, and Dr. Richard Lighty, the center's first director, introduced it to the trade in 1994.
Growing notes: Site this aster in full sun to light shade. (More sun will result in a tighter habit and the most flowers.) It is adaptable to various soil types and moisture levels, being perfectly happy on the dry side. Zones 4–8.
3. ‘Purple Dome’ New England aster
(Symphyotrichum novae-angliae ‘Purple Dome’)
The second aster in the Mt. Cuba Collection exhibits darker purple flowers on a tidy mound 18 to 24 inches tall. Its compact shape pulls double duty: First, it makes this aster perfect for the front of the border or even a container; second, it “makes any foliar issues not noticeable,” Sam explains. (This plant might develop powdery mildew by fall.) He also observes that the hardy and native ‘Purple Dome’ “brings to mind garden mums, but it’s so much better.” A favorite companion? Goldenrod, for the color combination.
Origins: Species New England aster is a tall plant native to open woods, mesic (moderately moist) prairies and streambanks of the Northeast, Mid-Atlantic, eastern Great Plains and the Interior West. ‘Purple Dome’ was introduced by Dr. Lighty in 1989.
Growing notes: Like ‘Bluebird’, ‘Purple Dome’ can take full sun or filtered shade and a range of soil types. However, it grows best with consistent moisture, a key different that comparing the natural habitats of the two asters’ different species suggests. Zones 3–8. More about 'Purple Dome' aster.
4. ‘Golden Fleece’ autumn goldenrod
(Solidago sphacelata ‘Golden Fleece’)
When we hear “goldenrod,” many of us picture tall, skinny wands weaving their way among similarly lofty prairie plants in a natural space or designed meadow. The cultivar ‘Golden Fleece’, though, “fills a funny niche for goldenrods,” says Sam. “It’s a dwarf, clump-forming form of this species.”
Growing just 18 to 24 inches tall and spreading 24 to 36 inches wide, it can mingle in a mixed bed, perform as a tall edging or weed-strangling groundcover or fill a large container. It blends equally well in formal and naturalistic spaces and its fall bloom sees it “absolutely mobbed” with pollinators, in Sam’s words. This cultivar earned Europe’s International Stauden-Union’s Award for outstanding new plants when it was introduced and it continues to go strong.
Origins: The species is native to woodlands and rocky fields of the Mid-Atlantic, Southeast and Lower Midwest. ‘Golden Fleece’ popped up as a chance seedling in North Carolina and, after evaluation, was introduced by Mt. Cuba in 1989.
Growing notes: Sam notes that this goldenrod will persist through a “wide array of conditions.” It can take part shade and dry soil, but it’s at its very best in full sun with regular moisture and decent soil. Zones 4–9.
