Summersweet (Clethra alnifolia) is a cold-hardy shrub that can be grown in zones 3-9. This moisture-loving shrub needs little preparation for winter other than a generous layer of mulch around its roots to retain moisture. In warmer regions where Summersweet does not go completely dormant, the occasional watering to keep the root zone moist may be necessary.
Protecting Summersweet in Winter
Summersweet is a cold-hardy shrub, able to withstand temperatures as low as -30°F depending on the variety. While some younger and smaller twigs can be damaged by the cold during the winter, an early spring prune will ensure that healthy new growth is produced once temperatures have warmed. To protect Summersweet from the cold, apply 2-3 inches of mulch around the root zone prior to winter. In warmer regions, Summersweet is more likely to be damaged by drought than cold, so checking the soil moisture regularly and water as necessary.
Cutting Back Summersweet For Winter
In colder regions, Summersweet will lose its leaves and go dormant in the winter. Pruning in the fall and winter is not recommended, and major pruning can be done in the early spring to encourage new growth. In warmer regions, Summersweet may keep its leaves and pruning can commence in the early spring as well.
Summersweet Winter Care in Pots
Perennials and shrubs in pots are always more likely to be damaged by extreme temperatures, regardless of their cold hardiness. In colder regions, we recommend placing potted Summersweet in a garage or basem*nt to protect its roots from the cold. In warmer regions, potted Summersweet can stay outdoors and regular watering may still be necessary.
Watering Summersweet in Winter
When in the ground, Summersweet will still do best in consistently moist soil through the winter. In warmer regions, this may mean checking soil moisture regularly and watering deeply as needed. In colder regions, dry roots are more likely to be damaged by extreme cold than those insulated with ice and snow. When warm days come about, check the soil moisture in your garden and water when needed.
When potted, only keep Summersweet outdoors if you are in a region with mild winters. Keep the soil consistently moist through the winter and avoid oversaturating the soil and leaving the roots soggy, which could lead to root rot. In colder regions, Summersweet in pots may still go dormant and not need any regular watering or care.
Growing Summersweet Indoors
Like many other perennials and shrubs, Summersweet is not well suited to be kept indoors long term. In the winter time to protect the roots, it is best to bring potted Summersweet into a dimly lit garage or basem*nt. This allows the plant to go dormant while still being protected from the cold. Flowering perennials and shrubs will often produce better blooms the following season if they are allowed a dormancy period. Keeping your shrubs in a garage will provide them with low enough temperatures to keep them dormant without the risk of damaging their roots.
Steps To Care For Summersweet in Winter
Summersweet is cold hardy and requires little care through the winter. Providing a layer of mulch around the root zone of Summersweet can help protect the roots through the winter in colder regions. The chances of you needing to regularly water this shrub depend on how mild the winters are in your regions. Other than watering in warmer regions, Summersweet can be left alone until the early spring when pruning can commence.
Step 1 - Add 2-3 inches of mulch
Step 2 - In warm regions, water when necessary
Step 3 - Prune in early spring
FAQs
Summersweet is cold hardy and requires little care through the winter. Providing a layer of mulch around the root zone of Summersweet can help protect the roots through the winter in colder regions. The chances of you needing to regularly water this shrub depend on how mild the winters are in your regions.
Should I deadhead summersweet? ›
Consider these tips for caring for your hummingbird summersweet plants. 1. Pruning: In late winter, after the threat of extreme cold has passed, deadhead blooms and trim back foliage to your desired shape. Pruning will encourage new growth in early spring.
Will summersweet grow in shade? ›
This sturdy native shrub is also remarkably adaptable, tolerating shade, soggy soil, and salty air, making it a valuable addition to woodland settings and coastal gardens.
Why is my summersweet not blooming? ›
Summersweet thrives in well-draining soil that stays consistently moist; if the soil is allowed to dry out too much when the buds are forming, Summersweet may put more energy into surviving rather than blooming.
How do you cut summersweet to the ground? ›
The best time to prune your summersweet is when it is dormant in early spring / late summer. You can selectively prune 1/3 of the branches, focusing on those heavy lower branches laying on the ground and any crossing branches in the center. Cut each branch all the way back to the base.
Does summersweet like wet soil? ›
It grows best in full sun to part shade and moist to wet soil. Use summersweet in rain gardens, shrub borders, narrow spaces and perennial gardens where its four-season beauty can be enjoyed. A bit more information: This versatile shrub, also known as Sweet Pepperbush, is generally trouble-free.
What is the best fertilizer for Summersweet? ›
Initially, the soil the plant is installed into should be amended to make it more acidic and to increase the amount of organic matter in the soil. Over time, the soils acidity should be supplemented with an acid-based fertilizer. A liquid fertilizer, like Miracid works well.
How does Summersweet spread? ›
Summersweet clethra is a native, deciduous upright shrub that typically grows between 4 and 8 feet tall and slowly spreads by sending up new shoots from rhizomes to form a small thicket.
Will deer eat Summersweet? ›
While summersweets are generally not a first choice for deer, they may nibble on them if food sources are limited.
What animals eat Summersweet? ›
Summersweet does attract some animals, however… hummingbirds, birds, bees, and butterflies love it! Despite being deer resistant, it is important to remember that deer will consume most plants when they are lacking more palatable options.
Plant summersweet with other rain garden plants like yarrow, Siberian iris, and marsh marigolds in full sun and in damp or boggy soil. Because Summersweet is not fussy about soil type or pH, it can also be grown basically anywhere in the garden as long as supplemental water is readily available.
Do hummingbirds like Summersweet? ›
A beautiful, versatile, compact shrub, with three-season interest. Glossy, dark green foliage is not bothered by pests or disease. In late summer it is covered with 6-7” creamy white flowers with a deliciously, spicy scent. The flowers bloom for many weeks attracting butterflies, hummingbirds and native bees.
How do you take care of a summersweet? ›
Once summersweet shrub is established, little care is needed. Water deeply during periods of drought, as this plant does not like to get too dry. Since the shrub blooms on new growth, pruning can be done without any harm to the plant. Pruning is a good way to rejuvenate the shrub following the harshness of winter.
How big does summersweet get? ›
Clethra 'Ruby Spice'
Green leaves turn gold in autumn. Grows to 6-8' tall & 4-6' wide.
Is summersweet invasive? ›
Is Summersweet clethra invasive? Clethra spreads through roots that are suckering and can form wide colonies. This expansive growth happens after about the third year the plant is in place. This rooting growth can be contained if placed in a confined area near a patio or sidewalk which will not enable root expansion.
How do you keep tropical plants alive in the winter? ›
The easiest way to overwinter most flowering tropical plants is to let them go dormant in a cool space. Let your plants rest in a cool place (40° to 50°F) with little or no light. Their leaves will gradually yellow and drop. They can then spend the winter in an unheated basem*nt, unheated garage, or even a cool closet.
How do you keep celosia alive in the winter? ›
If you live in an area that gets cold and dark during the fall and winter months, a grow lamp can help keep your celosia alive until things begin to warm back up. You can buy a grow lamp for as little as $20 online or at any greenhouse or gardening center.
Is Summersweet a host plant? ›
Wildlife: Summersweet is highly valuable to native wildlife. The flowers provide food for native bees, butterflies, and hummingbirds, and a variety of songbirds eat the seeds. It is a host plant for the Sweet Pepperbush Nola Moth.
How do you get rid of snow-in-summer plants? ›
Pruning. Pruning is crucial to controlling the spread of snow-in-summer. One way to prevent the spread is to remove spent blooms (and any potential seeds) right after the plant flowers. In addition, because snow-in-summer typically finishes flowering all at once, you can trim back the whole plant at one time.
