In spring, gardeners act like kids in a candy store, greedily stuffing everything we can get our hands on into the ground. Then the annual drought kicks in. For the rest of the summer, we pay for our botanical gluttony with back pain and water bills, hauling around hoses (or buckets from the rain barrels) in an effort to keep the cache alive. All this when the truth is: fall is often a better time to plant here in Maryland for a variety of reasons.
“It’s better for gardeners,” says Robin Hanway, UMD Extension Program Assistant for Kent County. Reprieved from summer’s Sarahan heat, we emerge from the AC into balmy autumn, ready for a little garden restoration, a horticultural mini makeover that benefits both the soul and the neighborhood. “Weed growth slows and there are fewer pests,” Hanway adds. So, the improvements you make now tend to last a little longer visually and require less tending.
“Cooler temperatures are [also] less stressful for plants,” Hanway notes. The hot, desiccating winds of summer have usually given way to something more temperate, so plants are able to retain more moisture. “And soil temperatures are still warm, which benefits root growth.”
The cool soil temperatures in spring, when most of us want to jump start the season (and are often too quick off the mark) can stunt growth. Low soil temperatures affect the ability of plants to uptake nutrients.
“When soil temperatures are below 45F, overall root growth is reduced, so fewer roots grow and reach nutrients,” says Jon Traunfeld, Director of the Home and
Garden Information Center at University of Maryland Extension. Whereas the warm ground in autumn encourages subterranean growth. “Trees, shrubs, and herbaceous perennials planted in September and early October typically have enough time to establish root systems and survive the winter,” he says.
Also in fall, plants aren’t trying to produce leaves and blooms, so they can devote all their energy to building those sturdy root systems.
“The plants are dropping all their leaves if they’re deciduous so they’re not supporting all the energy that goes into their leaves,” explains Michael Jensen, licensed tree expert in the State of Maryland and owner of Unity Nursery in Church Hill. In conjunction with the mention of leaf fall (which is where we get the old Anglo-Saxon term for autumn), Jensen encourages people to ‘Leave the Leaves.’ “It’s not related to fall planting” he admits, “but everyone blows the leaves away.” While clearing them off is perceived as tidy, he notes that it squanders nutrients that the tree has assiduously banked. “The tree has been taking up nutrients all season long. Then all that energy falls on the ground and releases all those nutrients back on the ground. So, if you’re blowing the leaves away, you’re removing all the [free] nutrients, and then going and buying fertilizer.”
In addition to being economical (and training the community to view the leaf blanket as beneficial rather than messy), the fallen leaves are also critical habitat for some pollinators, who are also bird food. So, leaving leaves means less cost and labor for the gardener, more butterflies, lightning bugs, and birds for the community.
Another benefit that planting in fall offers is free water.
“There’s typically more rain, so there’s moisture,” says Jensen. “In fall planting, the water requirement is significantly reduced.” Generally, new plants need about an inch of water a week to get established, an amount that can taper in winter, but does not diminish completely. “During winter you need to water sometimes if it has been very dry.”
Planting in fall also offers plants – tree, shrub, perennial – some less obvious but no less valuable opportunities to adapt.
“Going into winter, which is a nice rest period with a low stress level, you’re moving plants to a new place,” says Jensen. “They’re getting settled in so they’re adjusting to the soils, their new light conditions, and all while they’re not trying to produce leaves and blooms.”
Jensen says that, depending on the weather and winter, especially now that the effects of climate change have become so apparent, he plants until the ground freezes.
Of course, some things will perform well only if they’re planted in fall. For example, early flowering perennials like Hellebore and Peony and the cool-weather bulbs, corms, and rhizomes – Daffodils, Tulips, Bearded Iris, Allium, Crocus – which won’t bloom reliably unless planted in fall.
“They need about 12 weeks of 40 degrees [F] or so to develop root systems [before they bloom],” says Jay Hutchins, general Manager of Brent and Becky’s Bulbs in Gloucester, VA. “They also take in much more food in fall than in spring.”
In addition to being easier on the gardener and many of the plants, fall planting is easier on the wallet since most garden centers discount summer-blooming perennials, shrubs, and trees at the end of the season.
“There are sale plants at the nursery to clear the way for spring inventory later and reduce maintenance requirements in winter,” Hanway notes.
Lightning bugs on Echinacea
Fall planting offers more bang for our horticultural buck and smarter-not-harder work for gardeners. When the plants we’ve put in during September, October, and sometimes November are called on to produce their spring flush of leaf and bloom several months hence, they’ve had the opportunity to build up reserves on which to draw instead of having to hit the ground running, so the speak. The visible result: plants tend to be larger, lusher, and less susceptible to drought. Win-win.
On Friday, Sept 26, noon-2pm, The Kent County Master Gardeners are holding a plant and bake sale in Chestertown’s Memorial Park. Mums, natives, indoor plants, human food(!). Stop by, pick up a snack or two and something for you or for a friend’s garden. All proceeds benefit the program, which benefits Kent County in so many ways.
Longtime journalist, essayist, and garden writer Nancy Taylor Robson is also the author of four books: Woman in The Wheelhouse; award-winning Course of the Waterman; A Love Like No Other: Abigail and John Adams, a Modern Love Story; and OK Now What? A Caregiver’s Guide to What Matters, which she wrote with Sue Collins, RN.