Readying the Gardens for Winter
Posted by Aaron Barton on Sep 23rd 2021
As the sun continues to set earlier and earlier, residing at a lower angle in the sky and casting a distinctly autumnal light on the cooler days ahead, it is time to start thinking ahead to next season which starts with proper preparation this fall. Taking the time to prepare your garden for winter will give you a head start on next season, ensuring your plants are healthy and protected so they can come back beautiful and healthy next year.
Cut Them Back
While many gardeners prefer to cut back their gardens entirely to leave a clean slate for the spring, doing so is not always the best decision for the health of your plants or the many local pollinators that call your garden home. Many plants offer winter interest in the landscape with ornamental berries, exfoliating bark, or dried blooms, and can also serve as a food source for local songbirds and other wildlife. Read our blog about plants for backyard birding here!
For many plants, leaving the tops intact will aid in winter protection and survival by protecting their crowns, and their stems assist in catching and holding protective mulch layers and snow to serve as additional insulation during particularly cold winters, especially in windswept areas and areas with little snow cover.
However, there are some plants that reap little benefit if their tops are left intact and should be cut back to about three inches high after frost to avoid messy cleanup in the spring. Any diseased plants should also be cut back and disposed of, not added to your compost pile.
Plants that should be cut back in the fall include:
- Alcea (Hollyhock)
- Aquilegia (Columbine)
- Coreopsis (Tickseed)
- Delphinium
- Dicentra (Bleeding Heart)
- Geranium (Cranesbill)
- Heliopsis (False Sunflower)
- Hemerocallis (Daylilies)
- Hosta
- Iris
- Monarda (Bee Balm)
- Peonies
Plants that should not be cut back in the fall include:
- Achillea (Yarrow)
- Aster
- Bergenia (Pigsqueak)
- Chrysanthemums (Mums)
- Echinacea (Coneflower)—great for birds
- Gaillardia (Blanket Flower)
- Geum (Avens)
- Grasses
- Heuchera (Coral Bells)
- Syringa (Lilac)
- Panicle Hydrangea
- Penstemon (Beardtongue)
- Salvia (Sage)
- Tiarella (Foamflower)
- Weigela
Water, Water, Water
Even as the days and nights get cooler and cooler with crisp autumn air, your plants are still using water as they continue to grow their roots and prepare for the long winter ahead. Fall air can be particularly drying, especially following the dry, dry summer your plants have endured this year. Perennial plants, trees and shrubs will appreciate a good drink before the arid winter months. Be sure to keep your plants watered, about one inch of water per week, up until the first hard frost to make sure your plants are healthy and ready for winter.
Tuck Them In
Following a few hard frosts and when the ground is good and frozen for the year, it is time to tuck the garden in for winter.
Top dress garden beds with a layer of compost to get a head start on next season. When the ground begins to thaw in the spring, the compost will settle into the soil with the help of spring rains, providing a gentle nutritional jumpstart for your plants to start the season, while also giving your soil composition a boost.
Following the application of compost, it is crucial to tuck your plants in to keep them protected from frigid temperatures and avoid damaging freeze-thaw cycles or even early January thaws. Mulch your perennials with a substantial layer, at least six inches thick, of fallen leaves, rye straw, or marsh hay to provide insulation and keep ground temperatures consistent throughout the winter. Be sure to wait until the ground is fully frozen to prevent any mold or disease issues and avoid tricking your plants into thinking it is a balmy spring day and rousing them prematurely from their winter slumber. In the spring, be sure to check your gardens and remove the mulch when new growth begins to emerge. Keep some mulch on standby until our last frost date in the event that we have a late freeze, and your plants need some last minute protection.
Don’t forget about trees and shrubs! Be sure to keep watering trees and shrubs as well, especially any new plantings. Trees and shrubs with young tender bark are also prime feeding for deer and other critters. Protect young plants with a wrap of burlap or hard plastic to prevent feeding and avoid dealing with girdling and other issues down the road. Leave any tree pruning until the spring.
Divide and Conquer
Fall is also a great time to reflect on your garden design and performance and consider dividing perennials to keep borders tidy, plant structure tight, and prolific blooms. Cut, saw, or pull apart root balls, leaving at least two to three new shoots per segment. Plant at the same depth as the original plant divided and be sure to water in thoroughly until frost. Great candidates for fall division include Astilbe, Lilies, Irises (both Siberian and Japanese Iris), Peonies, Hosta, and Veronica. Check out our video about dividing and transplanting perennials!
Enjoy your gardens!
Always be sure to take time (with your favorite adult beverage) to enjoy the cool fall air and fall color before frigid temperatures and snow return! Also take time to think about what’s next in the garden. Here are a few of our favorite perennial gardening videos to keep you busy and inspired!
Preparing your Garden for Pollinators
Early Spring Blooming Perennials
Perennials for Late Season Blooms