Key Points
Evergreen shrubs and trees planted in fall aren’t able withstand winter dehydration.Taproot shrubs and trees are especially susceptible to freezing temperatures before properly established.Summer-blooming bulbs and tubers will almost always rot if planted in fall.
Just because the leaves are turning doesn’t mean it’s time to abandon your garden; this is the perfect season for planting bulbs and some perennials that will bloom beautifully come springtime. However, there are some perennials you should avoid planting in the fall.
“Planting is a stressful time for plants; they are more susceptible to temperature and moisture stressors,” says horticulturist Frank Clarke.
We spoke with two experts to find out which perennials you should avoid planting right now and why.
Meet the Expert
Frank Clarke is the agriculture and horticulture program lead for the Cornell Cooperative Extension of Cayuga County.
Ruth Carll is the state program leader in consumer horticulture and master gardener program for Rutgers Cooperative Extension.
Evergreen Shrubs and Trees
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The Spruce / Jayme Burrows
Winter is an evergreen plant’s time to shine—holding onto their vibrant leaves through the chilly weather and snowstorms—but that doesn’t mean that fall is their preferred time to be planted.
“Not all evergreens transplant in fall, even if they will be awake through the winter. Broad-leaf evergreens (think of any evergreen with a leaf rather than a needle) will not establish a strong enough root system to resist dehydration caused by winter wind and cold,” says horticulturalist Ruth Carll.
Both experts warn against planting evergreens such as boxwoods, evergreen magnolias, andromeda, nandina, arborvitaes, and rhododendrons in the fall. The dry and windy conditions of the fall make these plants more susceptible to drought stress, meaning they’re less likely to survive the winter.
“Gardeners are better off waiting until spring before planting these types of plants,” Clarke says, noting that soil temperatures around 50°F are a good litmus. “Humidity levels are higher, and more moisture is present during the spring, reducing the risk of moisture loss stress in evergreens.”
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Taproot Shrubs and Trees
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The Spruce / K. Dave
Taproot shrubs and trees are plants that have a large, main root from which other roots sprout to the side. These include magnolias, oaks, ginkgos, and pawpaws, all of which Clarke suggests you do not plant in the fall.
“Trees with taproots tend to recover and develop roots more slowly than plants with fibrous root systems. The taproots are susceptible to damage from freezing conditions,” he says. “It’s possible that taproot trees will not develop enough in the fall to survive the winter or may face injury.”
Instead, plant these in early spring when the roots will have all of spring and summer to establish themselves fully and survive the following winter.
Summer Bulbs and Tubers
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Photography by Alexandra Rudge / Getty Images
You might have heard that fall is the perfect time to plant bulbs; while this is true for spring-blooming bulbs like hyacinths and tulips, summer-blooming bulbs probably won’t survive to see their bloom period if planted in the fall.
“Summer-flowering bulbs have tender bulbs that cannot withstand winter soil temperatures. They should be planted in the spring and dug out in the fall,” Clarke says.
He suggests waiting to plant lilies, gladiolus, begonias, and dahlias until the springtime, and Carll agrees.
“Daylilies, dahlias, cannas, society garlic and other summer blooming bulbs are dormant now and will just rot if planted in fall,” she says.
Different Seasonal Stressors
“Planting in the fall means crops must establish themselves enough to handle dry winds and freezing conditions during the winter,” Clarke says. “When planted in the spring, the crops must establish themselves enough to tolerate high temperature extremes, periods of drought, and periods of extreme wetness.”
3 Questions to Know If You Should Plant in Fall
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ArtmannWitte / Getty Images
Whether a flower is a summer-blooming tuber or an evergreen shrub might not be top of mind when you’re excitedly shopping the nursery aisles, so these are a few good rules of thumb to follow when determining if your new plant can be planted in the fall.
Is it already asleep? “You don’t want to plant anything that is already dormant as it won’t be ‘inspired’ to grow roots while it is sleeping,” Carll says. She says the “no leaves, no planting” rule should guide you well.Does it like cold soil? “Fall plantings must be awake and like cool soil temps so that they grow roots before winter dormancy or slow winter growth,” Carll says.What do the pros suggest? If you’re unsure when to plant anything, Clarke suggests contacting the local cooperative extension office in your state.
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