While October and November may represent the swan songs of the summer garden, these are also the optimum months for looking to the future by planting perennial flowers, trees and shrubs.
Fall planting gives spring and summer bloomers the ideal span of dormancy to establish roots and acclimatize to soil and site. Cool air and still warm earth, accompanied by increased rainfall over the winter months, offer the ideal environment for plant establishment.
Defined as “regularly repeated or renewed,” the botanical term perennial encompasses both landscape basics such as trees, shrubs and grasses as well as a wide variety of flowers rewarding gardeners with years of encore appearances.
Perennials, from daisies to daylilies, have served as staples in Southern gardens for centuries, and local garden centers and the Birmingham Botanical Gardens have educated and encouraged a renewed interest in the value of perennials as “investment plants” in recent years. Area nurseries are offering an increasing selection of perennials, and the Birmingham Botanical Gardens Fall Plant Sale October 20-21 will showcase hundreds of reliable, and in some cases rare, varieties of plants suitable for our climate zone (bbgardens.org/fall-plant-sale).
Plant for successive bloom and foliage feature, from daffodils in February through dramatic purple salvias in autumn.
Many perennials have a short bloom season while claiming a permanent spot in the garden. Intersperse with annuals and herbs of varying colors and foliage textures. Early bloomers such as false indigo (Baptisia Australis), Lenten roses (Helleborus orientalis) and irises continue to add textural interest for months after flowers have faded.
Summer soldiers that don’t object to heat and drought include purple coneflower (Echinacea purpurea), catmint (Nepeta faassenii ‘Six Hills Giant’), and daisies (Leucanthemum superbum ‘Becky’ and ‘Alaska’).
Magnets for migrating butterflies in fall, salvias come in a variety of sizes and colors. Blue-purple indigo spires (Salvia farinacea x longispicata), bright red and white lipstick (Salvia greggii), and delicate, frothy Russian sage (Perovskia atriplicifolia) add height as well as color and are good choices for the center of a bed or border.
Group for impact.
Odd numbers from three to seven in a group provide more punch than single plantings.
Consider vines for walls and trellises.
Confederate jasmine (Trachelosperum jasminoides) will quickly cover a fence and remains evergreen. Vines planted from seeds, such as moonflower (Ipomoea alba) and passion flower (Passiflora incarnata), often reseed to come back year after year.
Bloom season care.
Pinching and deadheading perennials such as coneflowers, daisies and catmint will encourage continuing bloom. Many perennials, including irises, bulbs, daylilies and phlox, should be dug and divided every few years, giving gardeners the opportunity to share with friends. Rather than making a clean sweep of the late fall garden, allow foliage, particularly that of hollow stemmed perennials like daisies and coneflowers, to die back naturally.
Plant them but don’t forget them!
When planting perennials in fall, it is helpful to mark locations to avoid mistaking emerging perennials for weeds in spring.