New York ironweed. Photo credit: Mary Alice Koeneke
It always seems the growing season is short in comparison to the long, gray days of winter. We want our colorful flowers to last as long as possible before surrendering our gardens to the first frost. Native perennials provide an array of flowers that bloom late into the growing season and support pollinators. Fall-blooming perennials provide much-needed pollen and nectar for the western honey bee (Apis mellifera) before winter. They also support pollinators whose life cycles begin later in summer or ones that migrate, like the monarch butterfly (Danaus plexippus) or ruby-throated hummingbird (Archilochus colubris).
Finding native perennials that bloom from late summer to fall can be more challenging than finding plants suited for spring or summer, when there is a profusion of options in every nursery However, there are a number of interesting perennials that feed pollinators and produce a pre-frost burst of color.
Joe Pye weed
Joe Pye weed (Eutrochium purpureum) grows three to ten feet tall with masses of purplish-pink blooms providing nectar from August through September. Giant blue lobelia (Lobelia siphilitica) and its scarlet red relative, cardinal-flower (Lobelia cardinalis) grow one to four feet tall and provide nectar for many pollinators, including hummingbirds. New York ironweed (Vernonia noveboracensis) produces bright purple flowers and Culver’s root (Veronicastrum virginicum) has long plumes of white flowers. Both grow to six feet tall. All of these species do well in sunny to partly shaded areas with moist soils.
Mountain mints (Pycnanthemum spp.) are a group of aromatic, deer-resistant plants that are pollinator magnets, attracting honeybees, beneficial wasps, butterflies, and moths. They produce small pinkish-white flowers from August to September. Short-toothed, also called broad-leaved mountain mint (P. muticum) prefers full sun to part shade with moist, well-drained soil. Appalachian mountain mint (P. flexuosum) forms a clump and is slower to spread.
A variety of goldenrods (Solidago spp.) provide sprays of bright yellow blooms that are drought tolerant, deer resistant and good nectar sources. Goldenrods grow from one to four feet tall and flower until frost. You can find a wide variety of goldenrods that tolerate many light and soil conditions. Several to look for are zig-zag goldenrod (S. flexicaulis) for dry conditions as well as partial shade; gray goldenrod (S. nemoralis) is a short plant for dry, sunny conditions; and Solidago rugosa ‘Fireworks’ prefers moist, well-drained soils in full sun to part shade. Also, to correct a popular misconception, goldenrod does not cause hay fever, because it does not have air-borne pollen. The less conspicuous common ragweed (Ambrosia artemisiifolia) that blooms at the same time as goldenrod causes the allergic reaction called hay fever.
Asters (Symphyotrichium spp.) are another large group of flowering plants that bloom in late summer and fall often until frost. The group is diverse in color, height, and preferred growing conditions. New York aster (S. novi-belgii) and New England aster (S. novae-angliae) are perhaps two of the best known fall asters. Both have purple flowers and grow in full sun. New York aster prefers drier conditions than New England aster. Aromatic aster (S. oblongifolium) has light blue flowers often still blooming into late October or November.
After planting and enjoying your late summer and fall blooming natives, leave the seed heads for birds to feed on and the stems for overwintering bees to use. Keep leaf litter on the ground for overwintering butterfly larvae. Revel in the last colors of the season while feeding the pollinators!