25 Perennials to Cut Back in October
The weather is cooling and your perennials are getting ready to go dormant for the winter. Do you know which ones to cut back for the season? Take a guided tour with gardening expert Liessa Bowen to learn about 25 popular perennials to cut back in October to help clean up your garden before winter.
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Your perennial flower garden requires some regular care and attention throughout the year. In the spring, you might design your garden, select plants, and transplant new flowers. You spend your summer watering, weeding, and watching for pests. October is the season for cleaning up and cutting back some perennials before winter.
There are some advantages to cutting back your perennial flowers. Cutting away unhealthy plant materials helps tidy and clean up the garden. You’ll also be removing dead and diseased organic matter which helps prevent the spread of pests and diseases. Cutting back perennials can help prevent winter damage and encourage fresh spring growth.
However, cutting back isn’t necessary or even recommended for all perennials. Some plants provide ornamental value during the winter and can be left standing for winter interest. Others provide a valuable food source for foraging birds or shelter overwintering pollinators. And some plants benefit from standing vegetation left over the winter to protect the sensitive crown from frost.
As you prepare your garden for winter, let’s take a closer look at 25 favorite garden perennials you can cut back this October.
Asiatic Lily
botanical name Lilium spp. | |
sun requirements Full sun to partial shade | |
height 3 – 4 feet | |
hardiness zones 4 – 8 |
Asiatic lilies are beautifully showy true lilies that originated in Asia. You will find a vast array of colorful cultivars that grow well in a sunny plot with rich, well-drained soil. These extremely showy flowers are large, long-lived, and come in exquisitely bright colors. You’ll need to protect your Asiatic lilies from deer and rabbits, or you won’t need to worry about pruning them at all because the hungry herbivores will prune them for you.
Asiatic lilies bloom in the spring or early to mid-summer. For the rest of the growing season, their waxy green leaves absorb energy from the sun, building up strength for next year’s growth. Wait until after a hard frost that kills the above-ground vegetation, and prune your Asiatic lily stems to about six inches above the soil line.
Astilbe
botanical name Astilbe spp. | |
sun requirements Partial to full shade | |
height 2 – 3 feet | |
hardiness zones 4 – 9 |
Astilbes are herbaceous perennials that look fantastic in a shade garden. These colorful plants love shade and moist, well-drained soil. They bloom in early summer, and their feathery flower plumes attract a myriad of pollinators. After flowering, prune back the spent flowers if you prefer, or leave them standing for their interesting form and structure.
If grown in a warm climate or dry soil, these plants look pretty rough by late summer. Prune back unattractive browned foliage as desired. After the first frost, when everything has died back, cut back all the leaves and flower stems to just a few inches above the ground. For renewed spring growth, you can also thin overgrown clumps at this time.
Balloon Flower
botanical name Platycodon grandiflorus | |
sun requirements Full sun to partial shade | |
height 1 – 2.5 feet | |
hardiness zones 3 – 8 |
Balloon flower is a showy perennial with perky purple flowers that bloom at the height of summer. These plants have glossy, toothed leaves that line their upright stems. Before blooming, the flower buds form a balloon-like, air-filled pod that opens into beautiful deep purple, bell-like flowers.
Grow balloon flowers in your mixed perennial bed with plenty of sun and organically rich, moist soil. When the fall frosts have killed off the above-ground vegetation, it looks ragged and unappealing. Now is the time to prune it away, cutting the stems close to the ground and removing spent vegetation from your garden.
Bellflower
botanical name Campanula americana | |
sun requirements Full sun to partial shade | |
height 2 – 6 feet | |
hardiness zones 4 – 8 |
Bellflower is a tall wildflower native to North America. These plants grow naturally in moist grasslands, and they will be right at home in your pocket prairie or meadow garden. They prefer cooler climates and a plot with light shade and rich, moist, well-drained soil. Bellflowers are short-lived perennials that reseed themselves in ideal conditions.
When growing bellflower in your garden, deadhead spent flowerheads to encourage a longer blooming phase. When your plants are finished blooming, enjoy their lush green foliage. The entire plant will die back after the first fall frost, so you can cut them back to the ground at this point.
Bearded Iris
botanical name Iris x germanica | |
sun requirements Full sun | |
height 1 – 4 feet | |
hardiness zones 3 – 10 |
Bearded irises are familiar garden favorites. These showy, spring-blooming perennials grow from thick rhizomes that slowly spread just below the soil surface. These plants need full sun and well-drained soil to grow well.
These irises bloom in the springtime. Their colorful flowers come in just about every color for a full rainbow of possibilities. After their large, showy flowers bloom, the flower stalks should be cut back to the base. Leave the leaves, however, until late fall unless they are obviously diseased or damaged. Then, use sharp pruning shears to cut the leaves down to six to eight inches to overwinter.
Bee Balm
botanical name Monarda didyma | |
sun requirements Full sun | |
height 2 – 4 feet | |
hardiness zones 4 – 9 |
Bee balm is an herbaceous perennial wildflower native to eastern North America. This is a vigorous member of the mint family with vibrant scarlet red flowers. Hummingbirds and butterflies adore their summer blooms, making this an excellent plant for your pollinator-friendly landscape. You’ll appreciate the long blooming season and dash of color in your wildflower garden.
Like many mints, bee balm is susceptible to powdery mildew and by the end of the growing season, there’s a good chance your plant is showing signs of powdery gray leaves. Cutting back this perennial in October can help reduce disease risk.
Divide larger clusters every few years to help improve airflow, and prune back stems to just a couple of inches for the winter. Discard any mildew-infested stems so you won’t reintroduce this pesky fungal infection the following spring.
Blanket Flower
botanical name Gaillardia x grandiflora | |
sun requirements Full sun | |
height 1 – 3 feet | |
hardiness zones 7 – 10 |
Blanket flower, also commonly called gaillardia, is a short-lived herbaceous perennial that can also easily be grown as an annual. These clump-forming plants have a long blooming season and often flower continually throughout the summer and into fall. Their brightly colored flowers attract butterflies and other pollinators. After flowering, birds feast on the dried seedheads.
Grow your blanket flowers in a container, raised bed, or as a perennial border. They are drought tolerant and make a good addition to a xeriscape or rock garden. Deadhead spent flowers to encourage further blooms and extend its season. Once the first fall frost hits, however, go ahead and prune back your blanket flowers low to the ground. They’ll be back again for a repeat performance the following spring.
Blazing Star
botanical name Liatris spp. | |
sun requirements Full sun | |
height 1 – 5 feet | |
hardiness zones 3 – 9 |
Blazing stars are perennial wildflowers native throughout the United States. You’ll find different species and cultivars best adapted to different climates and regions. Blazing stars bloom in mid-summer. Their tall spikes of fluffy purple flowers are a pollinator magnet, attracting butterflies, bees, and hummingbirds. After blooming, their dense seedheads remain showy and continue to attract wildlife as foraging songbirds feast on the seeds.
Allow your blazing stars to remain standing in your garden until killed by the frost. At this point, it’s safe to cut the stems down to a few inches above ground level. Make sure your garden plot remains well-drained in the winter, as these plants don’t like soggy winter soil.
Catmint
botanical name Nepeta spp. | |
sun requirements Full sun | |
height 1 – 2 feet | |
hardiness zones 3 – 8 |
Catmint is a fragrant herb with minty foliage and showy flowers. This is a fantastic plant for a container garden or showy perennial border. Most catmint varieties have a long blooming period, and their showy flower spikes are guaranteed to attract pollinators. Like most members of the mint family, catmint is easy to grow and spreads freely. Deadhead spent flowers to keep your plants blooming and reduce self-seeding.
In the fall, wait until after the first frost to prune back your catmint. By this time, the foliage will probably look ragged anyway, so this is an ideal opportunity to clean up your mint patch. You can use this time to divide and thin overgrown clusters. Cut it low to the ground, and fresh new springs will emerge the following spring.
Columbine
botanical name Aquilegia spp. | |
sun requirements Full sun to partial shade | |
height 2 – 2.5 feet | |
hardiness zones 3 – 8 |
Columbine is a reliable spring-blooming perennial that you can cut back in October. There are columbine species native to both eastern and western North America, as well as numerous colorful cultivars. Their unusual flowers attract hummingbirds and insect pollinators. These plants are typically short-lived perennials, but they readily reseed themselves in ideal conditions.
Columbine is a great choice for a shaded woodland garden or raised bed pollinator garden. These plants perform well in full sun and moderate shade and prefer moist, well-drained soil.
Leafminers love columbine leaves, and you can prune off damaged leaves throughout the growing season. In the fall, go ahead and remove all the dead or damaged foliage to clean up your garden until they re-sprout in late winter or early spring, depending on your local climate conditions.
Corydalis
botanical name Corydalis lutea | |
sun requirements Partial to full shade | |
height 1 – 2 feet | |
hardiness zones 5 – 8 |
Corydalis is an herbaceous perennial for your shade garden. This hardy plant loves rich, moist, soil with good drainage. It’s best grown in moderate climates as it doesn’t tolerate harsh winters or hot, humid summers. The bright yellow trumpet-like flowers and showy foliage form a beautiful ground cover when you have several clumps growing together.
In favorable conditions, corydalis has a remarkably long blooming period for long-season appeal. When the flowers fade and the foliage starts to depreciate, it’s time to do some trimming. Cut the leaves and spent flowers back to the ground after they turn brown to help clean up your flower bed and prevent aggressive self-seeding.
Daylily
botanical name Hemerocallis spp. | |
sun requirements Full sun to partial shade | |
height 1 – 3 feet | |
hardiness zones 3 – 9 |
Daylilies are popular perennials that perform well in a variety of conditions. Grow them in full sun or partial shade with well-drained soil. Daylily cultivars are diverse and colorful. They all have long, thin, grasslike leaves and large, showy, summer-blooming flowers.
Daylilies grow in clusters and need to be divided every few years to help them maintain their vigor. In warmer climates, these plants may be evergreen, but in cooler climates, the foliage dies back after the first fall frost. Cut back browned, damaged, and dead foliage to the ground in October, and this herbaceous perennial will regrow in spring. If deer visit your garden, they will happily help you with pruning; daylilies are a favorite deer snack.
Hosta
botanical name Hosta spp. | |
sun requirements Partial to full shade | |
height 0.5 – 2 feet | |
hardiness zones 3 – 9 |
Hostas are popular shade garden plants for good reason. These hardy perennials have showy foliage that looks lush and healthy from early spring through fall. When hostas bloom in the summer, their bell-like purple or white flowers attract hummingbirds and pollinators to your landscape. Over time, clumps expand to be quite substantial and are easily divided to create more hosta clusters.
Keep the foliage on your hostas until it’s killed by the cold. You’ll then want to clear it away completely. Hostas attract slugs, and you don’t want to offer these garden pests any excuse to hang around over the winter, so dispose of your hosta leaves rather than leave them in the garden.
Japanese Anemone
botanical name Anemone hupehensis | |
sun requirements Full sun to partial shade | |
height 1.5 – 2.5 feet | |
hardiness zones 4 – 8 |
Japanese anemone, also called thimbleweed or windflower, is an herbaceous perennial native to Asia. This clump-forming plant makes a lovely border or edging plant. It blooms in the summer or fall, and its white, pink, or lavender flowers are showy and long-lasting.
When Japanese anemone is finished flowering, you’ll be able to continue to enjoy its attractive foliage, as long as your plants don’t dry out. The leaves will stay green longest in rich, moist soil and partial shade. Cut back the foliage to the ground after the first frost or when the foliage depreciates and is no longer attractive. Then, apply a layer of mulch to help your anemones endure the winter cold.
Penstemon
botanical name Penstemon spp. | |
sun requirements Full sun to partial shade | |
height 2 – 5 feet | |
hardiness zones 5 – 8 |
Penstemons are clump-forming perennials that make lovely garden plants. There are several species and cultivars to choose from so you can decide which will perform best in your climate and landscape conditions. Most penstemons do well with light shade and rich, moist, well-drained soil. Pollinators love these plants and your penstemon flowers will be buzzing with activity.
Penstemons bloom in spring and early summer. After blooming, their green leafy rosettes continue to add landscape appeal through the summer. The leaves die back after the first frost, or earlier if growing conditions are unfavorable. When the vegetation declines, it’s time to cut them back. Trim these plants low to the ground for their winter dormancy.
Peony
botanical name Paeonia spp. | |
sun requirements Full sun to partial shade | |
height 2 – 3 feet | |
hardiness zones 3 – 8 |
Peonies are easily grown in the right conditions. They prefer cooler climates and need plenty of sunlight with fertile, moist, well-drained soil. Healthy peonies are long-lived and happily bloom year after year for reliable garden color. These plants produce large, showy flowers in shades of white and pink.
Peony foliage will die back after the first fall frost. This is the ideal time to trim off the dead leaves and stems and tidy up your garden for the winter. Dispose of the cut foliage for a tidy look and remove any hiding places for insect pests and powdery mildew to overwinter.
Phlox
botanical name Phlox paniculata | |
sun requirements Full sun to partial shade | |
height 2 – 4 feet | |
hardiness zones 4 – 8 |
Garden phlox is a perennial wildflower native to eastern North America. It prefers cooler climates rather than hot, humid summers. These showy wildflowers bloom throughout the summer months. Their pale lilac-pink or white flowers are a welcome addition to many garden plots, especially in locations with organically rich, moist, well-drained soil.
Phlox spreads readily by self-seeding and rhizomes. Within a few years, you will have a large patch of phlox. Unfortunately, crowded plants are more susceptible to powdery mildew later in the summer. Thin crowded masses of plants each year and prune these plants back to the ground each fall to prepare them for winter and fresh spring growth.
Rose Mallow
botanical name Hibiscus moscheutos | |
sun requirements Full sun to partial shade | |
height 2 – 7 feet | |
hardiness zones 4 – 9 |
Rose mallow, also known as swamp mallow, is a large, shrubby perennial. This commanding wildflower is native to moist soils of the southeastern United States. It blooms from mid to late summer with huge pink or white, plate-like flowers. Pollinators love these plants, and you can use them to attract beneficial insects to your rain garden or wetland edge.
You’ll want plenty of space for a rose mallow plant. They can grow up to seven feet tall and approximately four to five feet wide. By late fall, they stop blooming and start looking ragged. October is the time to cut these perennials back to a few inches, but don’t worry about cutting them so low. These plants will re-emerge in the spring, and once the weather warms, they grow remarkably fast.
Salvia
botanical name Salvia spp. | |
sun requirements Full sun to partial shade | |
height 1 – 5 feet | |
hardiness zones 5 – 10 |
If you’re a fan of salvias, you may have more than one of these showy plants. There are many native salvias, non-native salvias, and colorful cultivars. Perennial salvias are hardy and easy to grow. These low-maintenance plants come in an array of different flower colors and bloom at different times during the summer and fall.
Keep your salvia healthy during the growing season by providing it with plenty of sunlight and well-drained soil. Deadhead spent flowers to encourage a longer blooming season. When these plants look worn out in the fall or after the foliage dies back after frost, cut the stems low. If you see fresh basal growth, leave that alone; just remove the old, past-season growth.
Shasta Daisy
botanical name Leucanthemum x superbum | |
sun requirements Full sun | |
height 1 – 4 feet | |
hardiness zones 4 – 9 |
Shasta daisies are popular garden perennials. They love full sun and tolerate a variety of soil types, as long as the soil is well-drained. These sturdy plants look great in containers, raised beds, and garden borders. Pollinators love them, and they make lovely cut flowers.
Shasta daisies spread into attractive clumps. The flowers bloom in mid-summer. You can prune the spent flowers or leave them standing to attract goldfinches and other small songbirds. Allow the foliage to stay standing until it dies back, either from prolonged summer heat or the first frost. When the foliage becomes brown and dead, cut it away and clean up your garden.
Siberian Bugloss
botanical name Brunnera macrophylla | |
sun requirements Partial to full shade | |
height 1 – 1.5 feet | |
hardiness zones 3 – 8 |
Siberian bugloss is an herbaceous perennial from the Middle East. This clump-forming plant prefers cooler climates and won’t enjoy long, hot, humid summers. Give it a shaded location in your woodland garden with rich, moist, well-drained soil. Siberian bugloss makes a great ground cover for a perennial edge or cottage garden.
After the first frost, your Siberian bugloss will look quite unappealing. Go ahead and clean up this plant by pruning it back to the ground. Remove the dead foliage and dispose of it. In the first warm days of spring, Siberian bugloss sprouts fresh greenery and is ready for another round of intense blue springtime flowers.
Silver Mound Artemisia
botanical name Artemisia schmidtiana ‘Nana’ | |
sun requirements Full sun | |
height 0.75 – 1 foot | |
hardiness zones 4 – 8 |
Silver mound artemisia makes a lovely foliage plant for a sunny plot with well-drained soil. This plant looks fantastic in a xeriscape or dry border plot. Its mound of silvery, frilly foliage adds a dramatic contrast to most other vegetation. Deer and rabbits avoid artemesias, so you can grow them freely without worrying about them being eaten by herbivores.
Your silver mound artemisia will grow through the warm months into a soft, rounded clump. The mid-summer yellow flowers add some interest, but these plants are primarily grown for their attractive leaves. Late in the season, however, the leaves die back and turn brown and gray. Go ahead and cut the stems back the plant to four to six inches tall and mulch around your plants to protect them for the winter.
Spiked Speedwell
botanical name Veronica spicata | |
sun requirements Full sun | |
height 2 – 3 feet | |
hardiness zones 3 – 8 |
Spiked speedwell, sometimes simply known as Veronica, is an herbaceous perennial native to Asia and Europe. This clumping perennial isn’t bothered by deer or rabbits and makes a great all-purpose plant for a sunny garden plot. Its tall spikes of purple, pink, or white flowers make a bold statement and attract pollinators during late spring and through mid-summer.
When your plants have finished their first round of blooming, cut back the flowering stems to encourage a repeat blooming in the fall. The basal rosette will continue to grow and support the plant until the first frost. After frost, the remaining foliage depreciates and looks unappealing. Go ahead and prune away any remaining foliage after the first frost to keep your gardening looking neat and orderly.
Sunflowers
botanical name Helianthus spp. | |
sun requirements Full sun | |
height 2 – 6 feet | |
hardiness zones 6 – 9 |
You’re probably familiar with the annual sunflower and its oversized, yellow flowers. There are several species of native perennial sunflowers as well. These make wonderful landscaping plants for your prairie or meadow garden. Birds and butterflies love sunflowers, and their showy blooms make great cut flowers.
Perennial sunflowers bloom in late summer or fall. Leave the spent flowerheads for the birds to pick apart. When your plants start looking ragged or flop over, you can cut them back to improve the look of your garden. Late fall is the ideal time to cut back the stems all the way to the ground for aesthetic purposes.
Yarrow
botanical name Achillea spp. | |
sun requirements Full sun to partial shade | |
height 1.5 – 3 feet | |
hardiness zones 3 – 9 |
Yarrow is a versatile plant that thrives in full sun and well-drained soil. Use it along a border, grow it in your xeriscape, or create a container garden. Pollinators love these plants so you can also use them anywhere you want to enhance your butterfly-friendly landscape.
Yarrow blooms in the summer, and depending on the variety you have, the flowers may be white, yellow, peach, pink, purple, or scarlet red. When the flowering umbels fade and turn brown, prune those away so you can focus on the delicate, fern-like foliage for the rest of the year. Cut back the stems and dead leaves in late fall to keep your garden tidy. Fresh new foliage emerges in early spring.
Frequently Asked Questions
Are there reasons I shouldn’t cut back some perennials in the fall?
Some perennial flowers should be allowed to stand through the fall and winter. The following perennials survive winter weather better if left intact during the winter. Their foliage will help protect the sensitive crowns during cold weather. Anise hyssop, red hot poker plant, and hardy geraniums are a few examples.
Some plants provide excellent forage for winter birds. The birds relish the seeds of these plants, so you can leave them standing as a natural bird feeder. Birds love black-eyed Susans, purple coneflowers, and other coneflower varieties. Similarly, leave your milkweed plants standing over the winter to protect any overwintering pollinators and caterpillars that might be sheltering there.
Plants with evergreen foliage don’t need to be pruned back. If you live in a favorable climate for these plants to remain evergreen, don’t prune off their green leaves in the fall, just trim away or dead and dying vegetation. Some examples include coral bells, ferns, hellebores, moss phlox, and cranesbill geranium.
Finally, some plants simply look interesting during the winter months. You can keep some winter interest in your garden by leaving these long-lasting decorative plants standing: false indigo, stonecrop, and ornamental grasses.
How far down should I cut back my perennials?
There’s really no “one-size-fits-all” rule. A general rule of thumb is to leave two or three inches of stem above the soil. This will help you find them in the winter and spring. For plants that have very soft stems that die back completely, you can remove the entire above-ground portion. For some plants with sturdy stems, you might want to leave them a little taller for winter interest.
When should I cut back my perennials?
Don’t be in a huge rush to prune your plants unless they are diseased or already dead. Depending on your climate zone, your timing may be different. Generally, you’ll want to wait until after the first frost or two to prune back perennials. Until the top of the plant is completely dead, the roots are still gathering energy from the rest of the plant.
What tools should I use for cutting back my perennials?
Every gardener should have a pair of comfortable gardening gloves. For smaller stemmed plants, a sharp hand-pruning tool is extremely useful. For broad-leaved plants like irises, sharp, broad-bladed garden shears or hedge shears are useful for cutting through the leaves.