|The temperatures are dipping and the leaves are changing colors, but that doesn’t mean the gardening season is over. For the enthusiastic gardener, there is still plenty to enjoy in the garden well into late fall and winter.
Spring may get the glory for the abundance of flowering trees and bulbs that follow the bare winter landscape, but there are plenty of flowers that will shine well past Labor Day.
One of the most obvious flower choices for late-season bloom are those in the Aster family. Most asters are going to fall in the color scheme of lavender to white, but in habit and bloom time they vary greatly. You can create an astounding sea of lavender-blue blooms from late summer into late fall by combining varieties with different bloom times and habits- for instance ‘Monch’ Aster to bloom in the middle of a border in August and September, followed by the shorter ‘Little Carlow’ Aster from September to October, and finally the large ‘Raydon’s Favorite’ Aster to carry the bloom from October into November.
Some Asters, such as ‘Snow Flurry’ Heath Aster, only grow a few inches tall and can spread out as a groundcover that will be blanketed with starry white blooms in September and October. Others, like Tatarian Aster or our native Frost Aster, both of which can reach over 6 feet tall, lend an imposing structure to the back of a border.
Another perennial flower that can be dramatic in the fall landscape are the hardy garden mums. Related to the common mums that you can buy at the garden center this time of year, these flowers are reliably hardy in the landscape, where they take on a more relaxed, open habit than their garden center cousins. They begin to bloom in late September and will keep on going until the first frosts. ‘Hillside Sheffield’s Pink’ is one of the best known and most planted varieties. It produces masses of starry, apricot-pink blooms. ‘White Bomb’ is another variety, whose low growing habit makes it a good choice for a flowering groundcover. Other varieties include the soft orange ‘Campfire Glow,’ and the lavender ‘Cambodian Queen.’
Other late flowering perennials for the fall garden are the Rudbeckias. There are many varieties of this old-fashioned favorite, but for late season bloom, Rudbeckia fulgida or ‘Brown Eyed Susan’ is the best. There are cultivars such as ‘Goldsturm’ that will begin to bloom in August and others such as R. fulgida var. fulgida that will bloom until late October.
Another impressive fall flower is Monkshood. While not quite as easy maintenance as the previous mentions, if given a sheltered space with plenty of moisture, Monkshood blooms in October and November with extraordinarily intense blue flowers.
No discussion of Autumn interest in the garden would be complete without taking into account the brilliant colors of senescent leaves. One of the most striking examples of perennials with great fall color is Arkansas Bluestar (Amsonia hubrichtii), whose thread-like foliage takes on intense hues of orange and bright yellow in October and November. Blue Leadwort (Ceratostigma plumbaginoides) and Creeping Raspberry (Rubus calycinoides) are two groundcovers that take on vivid red shades as the days get cooler. Beardstongue and Sedum are two other perennials with exceptional fall color. Many shrubs also have striking fall pigments. Summersweet (Clethra alnifolia) turns bright yellow, ‘Autumn Jazz’ Viburnum (Viburnum dentatum ‘Autumn Jazz’) takes on hues of yellow and burgundy-red, and Virginia Sweetspire (Itea virginica) turns intensely, fiery red.
Evergreens, too, can begin to take center stage at this time of year. Brightly variegated leaves, such as those on ‘Goshiki’ False Holly or Variegated Aucuba can come to the forefront of the garden as summer fades, as can the myriad textures and colors of evergreen False Cypress (Chamaecyparis spp.). Some evergreens, such as ‘Gulftide’ Osmanthus, with its profusion of tiny, honey-scented, late fall blooms, or Sasanqua Camellias with their beautiful flowers in shades of red, pink and white, can carry a garden’s flowering season until well past frost.
In fall and early winter, ornamental grasses can provide considerable visual interest in the garden. Strongly vertical grasses such as Big Bluestem, Indian Grass or ‘Karl Foerster’ Calamagrostis can provide an interesting backdrop for fall blooming perennials. Arching, fountain-like grasses like ‘Skyracer’ Moor Grass or ‘Dewey Blue’ Panic Grass can look spectacular with the sun sparkling through their airy seed heads.
The spent seed heads of summer’s perennial flowers can also provide interest in the late season landscape. Not only do songbirds, such as goldfinches, love the seeds of Coneflower and Rudbeckias, but the dried seeds heads of these and other flowers take on a new visual significance as the season progresses and they begin to take on the dew and the frost, catching and reflecting light in all directions. Leaving these structures up throughout the late season is also helpful for the praying mantises who lay their eggs on the stems, and the moths such as the Luna and Emperor.
The garden doesn’t quit just because temperatures are getting chilly. With a little planning and an eye for how the features of a space may progress through the seasons, our landscapes can be places of extraordinary beauty throughout the year.