This group of late bloomers includes reliable plants such as tall Sedum 'Autumn Joy', a garden workhorse whose rosy broccoli-like flowers are bee magnets in the fall. Newer sedum selections, such as 'Matrona' and 'Black Jack' with their burgundy-tinged foliage and 'Frosty Morn' with its green-and-white variegation, offer extra interest.
The various "Helis"—Helianthus, commonly known as sunflower, Heliopsis, common name oxeye, and Helenium, also called sneezeweed or Helen's flower—are additional stalwarts of the late-summer to early-fall garden, blooming in yellows, and in the case of Helenium, shades of orange, red and rust as well. Perennial asters in purples and pinks are cooler color options for later in the season.
Besides these mainstays, there are several lovely but surprisingly less well-known perennials that can provide flowers and structural interest in the autumn garden.
Late-Blooming Perennials to Get to Know
Japanese anemones are elegant fall bloomers that prefer a moist and semi-shady spot. (These spread, so site them carefully.) From a mound of grape-like leaves, rise tall stems topped with fresh and delicate single or semi-double blooms in pinks, purples and whites.
A favored plants is Cimicifuga (various species and cultivars), whose common names include black snakeroot and bugbane. Though most are quite tall, they are not space hogs, nor do they require trussing up like a delphinium. Rich, moisture-retentive soil and part shade will encourage the best showing from their finely-cut leaves and fragrant white flower spikes. Several varieties feature maroon foliage.
In moist soil, Chelone, or turtlehead, grows into a 3 ft. (0.9m) glossy clump with pink or white flowers that resemble a snapdragon or, as its name suggests, a turtle's head. It's not quite the visual knockout that Cimicifuga is, but it is strong and upright (even stiff) when so much of the garden has finished or flopped. Joe Pye weed (Eupatorium species and cultivars) are tall plants, native to North America, that remind one of refined milkweeds. They prefer moist soil, and their flattish flower clusters are very attractive to butterflies. Commonly available cultivars include E. maculatum 'Selection' or 'Gateway', both with pink flowers, E. fistulosum 'Bartered Bride', with white flowers, and E. rugosum 'Chocolate', with brownish-purple foliage and white flowers.
If you saw a single blossom of the sweet autumn clematis (which may be labeled as Clematis terniflora, C. ternifolia, C. paniculata or C. maximowicziana), you would not likely rush out to buy one. But see that blossom en masse with hundreds of others in a long-lasting fragrant white cloud, and you'll be hooked. This approximately 15 ft. (4.5m) vine flowers on the current year's growth in early autumn and pairs beautifully with fall-red Virginia creeper (Parthenocissus quinquefolia).
Bulbs That Provide Fall Color
Spring jumps to mind with the words bulb and corm, but some hardy fall bloomers are also available. One of these is the lovely Colchicum autumnale, whose common names are autumn crocus (though it is not a crocus) and naked ladies, since the pink, lavender or white flowers emerge without foliage, which comes the following spring.
There are many additional fall-flowering perennial and bulb choices. An autumn visit to our store will give you some ideas for alternatives to potted mums that will carry your perennial garden through to the frost with freshness, structure and color.