21 Perennials You Shouldn’t Cut Back in Fall
While many plants benefit from a good fall cutback as they prepare for winter, some perennials are better left standing. They bring winter insulation, forage for birds and wildlife, shelter for pollinators, and unique attributes for lasting seasonal interest. Explore which perennials should not be cut back this fall with gardening expert Katherine Rowe.
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Fall is here, and so is the time to relish cooler temperatures, seasonal transitions, and autumnal hues. After a few heavy frosts, we look to tidying up, tending to perennials, and tucking the garden in for winter. But some perennials shouldn’t be cut back in the fall. Their foliage and stems offer winter insulation for the crown, especially helpful for marginally hardy growers in cold climates.
Those with showy seed pods and fruits provide lasting winter interest and forage for songbirds. Leaves and branches become nesting and shelter sites for overwintering pollinators. Semi-evergreen growers add a bit of green to the quiet landscape.
There’s a balance between cutting back herbaceous perennials to prevent fungal disease and leaving woody specimens standing. Go ahead and cut back perennials like tall garden phlox, monarda, yarrow, and hostas. Do a final deadheading sweep for any you don’t want to self-seed.
Consider leaving those with added benefits, whether for plant health, unique interests, or ecological services. It may take revising our aesthetic a bit to appreciate the value of standing perennials, but they bring life to the resting garden, even in dormancy.
Coreopsis
Coreopsis Seeds
Anise Hyssop
Anise Hyssop Seeds
Common Milkweed
Milkweed Seeds
Echinacea
botanical name Echinacea purpurea | |
sun requirements Full sun | |
height 2-4’ | |
hardiness zones 3-9 |
Echinacea is a prime one to leave standing. It offers fall and winter value in showy seed heads that provide forage for birds and wildlife. The hollow stems and dried leaves become nesting cavities for native bees and other insects. Plus, seeds require cold stratification to germinate in the spring, so leaving them to drop and disperse brings the best chance of expanding the colony.
A natural prairie plant, coneflower is a native perennial that flourishes in the summer heat and full sun. It grows in a variety of climates and does best in well-draining soils.
Echinacea features a long bloom season with lasting purple ray flowers. The prominent orange central discs are a nectar source for beneficial insects.
Rudbeckia
botanical name Rudbeckia fulgida | |
sun requirements Full sun to partial shade | |
height 18-24” | |
hardiness zones 3-9 |
Like coneflower, black-eyed Susan has hollow stems well-suited to pollinator overwintering. Its seeds, too, provide food as other sources become more scarce. Seeds benefit from winter cold exposure to sprout in the spring.
Rudbeckia is a long-blooming prairie wildflower native to the southern, central, and western U.S. It thrives across growing conditions, including heat, humidity, cold, and drought.
The easy-care perennial blooms nonstop from summer through frost. Its golden ray flowers and distinguishable chocolate button centers make a cheerful mass planting.
Milkweed
botanical name Asclepias spp. | |
sun requirements Full sun | |
height 2-6’ | |
hardiness zones 3-10 |
Butterfly milkweed is a heat-loving performer whose seeds benefit from cold and moist stratification. As plants finish blooming, collect the seeds or let them drop naturally to increase numbers and feed the birds. When seed pods split open in the fall, birds use their silky fibers for nesting material.
Let stems remain intact to shelter insects, another of milkweed’s many offerings in addition to nectar, pollen, seeds, and role as monarch host. During the growing season, milkweed is a food source for monarch caterpillars and shelter for their chrysalis.
Monarchs rely on masses of blooming milkweed in the summer. Their rich blossoms also draw beneficial insects.
Coreopsis
botanical name Coreopsis spp. | |
sun requirements Full sun to partial shade | |
height 2-5’ | |
hardiness zones 3-9 |
Coreopsis offers extended interest as one of the last flowers to fade at the season’s end. From spring to fall, it’s a favorite nectar and pollen source for bees and butterflies.
Songbirds forage on the seeds in fall and winter. It reseeds readily in the landscape for a drift of sunshine yellow at its peak in mid-summer.
Lance-leaved coreopsis (Coreopsis lanceolata) is the most common species with feathery golden ray petals with yellow centers. C. lanceolata is winter-hardy, thrives in heat, and is drought-tolerant. Some regions of the world host evergreen coreopsis plants, and cutting them down reduces the amount of greenery you’ll have in winter.
Heliopsis
botanical name Heliopsis helianthoides | |
sun requirements Full sun to partial shade | |
height 2-5’ | |
hardiness zones 3-9 |
Heliopsis, or false sunflower, has stiff, sturdy, multi-branched stems perfect for cool season perches. From summer through frost, vibrant yellow flowers with fuzzy centers buzz with pollinators. Birds eat the seeds post-bloom, and leftovers self-seed.
Heliopsis is a rugged grower native to the central and eastern United States. It’s also highly ornamental, brightening the border all summer with tall stems. Dwarf cultivars are perfect for container culture.
Switchgrass
botanical name Panicum virgatum | |
sun requirements Full sun to partial shade | |
height 3-7’ | |
hardiness zones 5-9 |
Switchgrass and other ornamental grasses, with their plumes and graceful blades, provide visual interest that persists through winter. A shimmer of frost on the tufts is a beautiful sight. The dried leaves and seedheads are also a haven for birds and small mammals for food and shelter.
Switchgrass is a native North American prairie grass that grows across varying soil types, moisture levels, and light conditions. The blades turn yellow and tawny in the fall and add movement and sway to the cool-season landscape.
Keep ornamental grasses intact until late winter or early spring before new growth emerges. Switchgrass is tough, preferring lean soils to overly rich ones. It grows in wet and dry situations and tolerates occasional flooding. Look to ‘Northwind’ for a variety with ornamental leaves that form an upright column for vertical interest.
Chrysanthemum
botanical name Chrysanthemum spp. | |
sun requirements Full sun | |
height 1-3’ | |
hardiness zones 5-9 |
Hardy chrysanthemums do best with winter protection in cold zones. Wait to cut back stems until early spring as new growth emerges. The leaves and branches that remain post-bloom help insulate the crown through freezing conditions.
For further protection, mulch around plants and lightly among the crown. Evergreen boughs give further insulation to the marginally hardy perennials susceptible to exposure through frost heaving (the soil’s natural freeze and thaw cycles).
Mums are easy-care in ample sunshine and moist soils with good drainage. They produce a spectacular blanket of blooms in autumnal tones. Foliage is soft and textural for multi-season appeal until dormancy.
Caryopteris
botanical name Caryopteris spp. | |
sun requirements Full sun | |
height 3-4’ | |
hardiness zones 5-9 |
Caryopteris (also bluebeard or blue mist) is shrubby with attractive leaves and abundant tiny blue flowers in late summer and fall. In winter, its thick, woody stems are susceptible to dieback. Wait to prune until late winter before new growth develops for flowering.
Caryopteris is striking in flower but handsome with foliage alone. Caryopteris x clandodensis creates a misty spray of blooms. ‘Gold Crest’ has showy bright green-gold leaves, while ‘Dark Knight’ has deep royal purple petals above silver-blue foliage. C. divaricara ‘Snow Fairy’ has mint green leaves with a white margin and a cloud of deep lavender blossoms.
Caryopteris grows well in average, medium-moisture soils. It prefers loose loams and sandy conditions and tolerates periods of dryness but not prolonged saturation.
Sedum
botanical name Sedum spp. | |
sun requirements Full sun to partial shade | |
height 3”-2’ | |
hardiness zones 3-9 |
Sedum, or stonecrop, brims with autumnal interest in exciting colors and textures. Usually blooming in summer and early fall, the late-season flowers bring color-changing qualities as they mature and food for bees, butterflies, and birds.
Post-flowering, the seedheads last well into winter. Fresh or dried, they make beautiful floral arrangements and accents. Let them persist on the stem for extended landscape interest.
Sedum offers multi-season appeal, whether a low-growing ground cover or a tall, upright specimen. Drought-tolerant with succulent qualities, stonecrop needs well-draining soils to thrive. The seeds need cold stratification for strong germination.
Joe Pye Weed
botanical name Eutrochium purpureum | |
sun requirements Full sun to partial shade | |
height 5-7’ | |
hardiness zones 4-9 |
Joe Pye weed is another hardworking multi-tasker. In summer and fall, domed purple-pink flower clusters become landing pads for butterflies and beneficial insects. Dark, attractive seed pods last well into winter. Hollow, pithy stems and dried leaves create nesting cavities for native bees and others.
The coarse, long leaves are dark olive green with purple-hued leaf nodes. Native to southeastern Canada and central and eastern U.S., Joe Pye weed isn’t as aggressive as the name implies, though they grow carefree in challenging sites.
The ornamental and ecological value benefits the native, pollinator, naturalistic, and rain garden. Leave Joe Pye standing for a sweep of cold season enrichment.
Liatris
botanical name Liatris spp. | |
sun requirements Full sun to partial shade | |
height 1-5’ | |
hardiness zones 3-9 |
Blazing star liatris may look a little scrappy at season’s end, but its tall bloom spikes, even when faded, provide vertical interest, especially in a naturalistic group. The chickadees and finches that perch and feed on the dark brown seeds enliven the scene.
Blazing star blooms from July to September on stiff, upright stems that reach up to five feet tall. Uniquely slender and dense flower spikes in purples, pinks, and whites rise from arching, bladed foliage. The cold-hardy performers are native from Canada to Florida, depending on the species.
Hardy Geraniums
botanical name Geranium spp. | |
sun requirements Full sun to partial shade | |
height 1-2’ | |
hardiness zones 3-8 |
Hardy geraniums, or cranesbill, feature softly mounding, semi-evergreen foliage. The palmate leaves are attractive year-round. Avoid clipping them in the fall to allow a pop of rich green in the frosty garden.
Some cranesbills bloom in spring and early summer, while others last into autumn. Geranium ‘Rozanne’ is a top-performing hybrid with bright purple-blue flowers from spring and early summer and free flowering through fall. For its long bloom time and vigor, ‘Rozanne’ won the Perennial Plant Association’s Perennial Plant of the Year and the Royal Horticultural Society’s Award of Garden Merit.
Hardy geraniums naturalize under optimal conditions but aren’t aggressive or invasive. These low-maintenance growers don’t require deadheading.
Russian Sage
botanical name Salvia yangii | |
sun requirements Full sun | |
height 2-4’ | |
hardiness zones 5-9 |
Russian sage, with its silvery stems, delicate gray-green foliage, and sprays of purple-blue blooms, benefits from winter protection so it can shine in summer. Let stems remain in place to insulate the crown through freezing conditions.
Russian sage is a reliable bloomer from summer ‘til frost. It received the Perennial Plant Association’s Perennial Plant of the Year award for its performance across various growing zones.
For best growth, provide full sun and well-draining soils. Russian sage performs beautifully in hot and dry conditions.
Prairie Coneflower
botanical name Ratibida columnifera | |
sun requirements Full sun | |
height 2-3’ | |
hardiness zones 4-9 |
Prairie coneflower, with its prominent central discs and drooping ray petals, make a fine dried feature in the chilly border. Finches and sparrows, among others, delight in its lasting kernels.
The North American natives are long-blooming, with unique yellow or scarlet petals and bright gold edges. The central cone is greenish brown, and insects enjoy the nectar and pollen.
Prairie coneflower is fast-growing, drought-tolerant, and withstands competition from other plants. It grows aggressively in optimum growing conditions and outcompetes weaker growers. Deadhead in late summer while leaving some stems in place if you have the space.
Rose Mallow
botanical name Hibiscus spp. | |
sun requirements Full sun | |
height 3-5’ | |
hardiness zones 5-9 |
Leave rose mallow, or hardy hibiscus, standing to provide winter interest with upright branching and perches for wildlife. Give plants a heavy layer of mulch as temperatures drop to retain moisture and insulate roots. Cut them back in the spring before new growth emerges. New growth is slow to appear, but once it does, it develops quickly for summer flowering.
Hardy hibiscus are low-maintenance, easy-care growers for years of recurrent tropical-looking blooms. Exceedingly showy, the perennials yield huge disc flowers with tissuey, overlapping petals among textural foliage.
Hardy hybrids stem from North American native mallows (H. moscheutos, H. laevis, and H. coccineus), bred for improved landscape durability and hardiness. Flowers appear from mid-summer through fall and range from pale pink to deep scarlet.
Red-Hot Poker
botanical name Kniphofia uvaria | |
sun requirements Full sun | |
height 3-4’ | |
hardiness zones 5-9 |
Red-hot poker benefits from winter protection in zones 5 and 6. Employ mulch or leaf litter, or tie leaves together as an insulating canopy to protect the crown from freeze damage. Keep the slender-bladed foliage as a blanket of coverage.
Red-hot poker blooms in “torches” in late spring and early summer. The red buds and blooms on tall spikes transition to yellow for a multi-toned appearance.
Succulent Kniphofia spreads through clump-forming rhizomes. It does best in organic soils with good aeration and drainage.
Swamp Sunflower
botanical name Helianthus angustifolius | |
sun requirements Full sun to partial shade | |
height 5-8’ | |
hardiness zones 5-10 |
This perennial sunflower has tall, branching stems with clusters of yellow daisy-like flowers that give way to nutritious seeds. The branches are tall and make good perches.
Swamp sunflowers are an excellent food source for birds and specialized bees and a host plant for the silvery checkerspot butterfly. Ruffed grouse, quail, and small mammals forage on the seeds.
Plants bloom in late summer and fall for a late-season show of bright gold. They span the seasons with loose, naturalistic appeal.
Anise Hyssop
botanical name Agastache foeniculum | |
sun requirements Full sun | |
height 2-4’ | |
hardiness zones 3-9 |
Anise hyssop is an old garden favorite with loads of purple-blue tubular blooms. It flowers profusely in summer through frost and is a rich nectar source for bees, butterflies, hummingbirds, and more.
To get the best out of the herb, prune it in early spring as new growth appears. This protects stems from cold exposure and dieback. It also promotes insect overwintering opportunities.
Deadhead spent blooms in the summer to enjoy a round of late-season flowering. The dried flowerheads will support birds like finches, juncos, and sparrows all winter.
Sunflowers
botanical name Helianthus spp. | |
sun requirements Full sun | |
height 1-15’ | |
hardiness zones 2-11 |
Sunflowers bloom from summer into fall, matching the harvest palette in yellow, garnet, and ivory. While they may look a little gnarly post-frost when spent, brown, and dry, the benefits of the nutrient-packed seedheads that support busy birds and small mammals outweigh the short-term aesthetics.
To maximize their impact, plant sunflowers in groups and seed two to three successional plantings so that when one group fades, another takes its place. Sow up until four to six weeks before the anticipated first frost.
Globe Thistle
botanical name Echinops bannaticus | |
sun requirements Full sun to partial shade | |
height 3-4’ | |
hardiness zones 3-8 |
Globe thistle produces striking blue globes on tall stems in mid-summer through fall. The stiff, structured blooms are unique on the stem and make excellent fresh or dried floral arrangements. The seed-filled rounds provide late-season forage and winter appeal with dried flowerheads that remain upright.
In the warm season, the tiny florets that form each globe attract bees, moths, and butterflies. Silvery-green foliage heightens visual interest.
Globe thistle tolerates poor soils with good drainage. If reseeding is an issue in your growing space, deadhead throughout the season (and to promote flowering). Leave the remainder in autumn for wildlife and beauty.
Coral Bells
botanical name Heuchera sanguinea | |
sun requirements Full sun to partial shade | |
height 1-2’ | |
hardiness zones 3-9 |
Coral bells are semi-evergreen, depending on climate. They’ll grace the chilly border with colorful foliage and dynamic mottling. Leave the leaves for this reason and to protect the crown. Even faded stems and foliage give added protection in cold conditions.
The North American natives have attractive green leaves and summertime bloom sprays in pinky-red, with hybrids in lime, purple, bronze, red, and silver foliage. Plant them in September and October for all-season beauty.
Heuchera needs rich, organic, well-draining soils. It’s relatively drought-tolerant once established.