Temperatures are finally starting to chill, but savvy gardeners aren’t packing away the spade and clippers just yet. Gardens can stay vibrant far into fall, and the cooler season is an excellent time to grow leafy greens and prepare for next spring.
Start with chrysanthemums, autumn’s signature flower. Unless you’re holding a party or special event, purchase plants with buds rather than full blooms to prolong your enjoyment.
Most varieties at garden centers may bloom next year, if the winter is mild and you give a little care. “Stick it in the ground and you’re good to go,” says Robert Scanzaroli, a senior gardener at Longwood Gardens. Add some mulch to dress them for winter. Next spring and early summer, pinch back the growth until July 4, after which buds will start to form.
More tender mum varieties, such as the ones on display in Longwood’s conservatory, should be treated as annuals. Once they’ve faded, that’s that.
Asters, like most mums, have a chance of coming back in spring. Again, pinch them back to avoid leggy plants that bow toward the ground come autumn.
Though asters and mums are among the most popular fall flowers, pansies in recent years have come on strong. The perky flowers’ striking hues accent the oranges, browns, reds and yellows typically associated with fall, Scanzaroli says. And if Delaware experiences a moderate winter, the pansies might pop up in spring, says Lorene Athey, a landscape architect and owner of Guided Path Planning & Garden Design in Newark.
Fireworks, a cultivar of goldenrod, is aptly named. “It’s basically a fireworks display when it opens up,” Scanzaroli says. “It’s an amazing plant.” If you can’t find any at this time of year, snatch some up next spring in anticipation of fall.
Ornamental grasses come into their prime in fall. Shenandoah, for instance, turns a wonderful wine color in September. As with goldenrod, you may need to purchase grasses earlier in the season to plan for fall. If you find some on sale this year, it’s a good time to plant and let them develop for display next year.
For a lively accent, consider Chinese five-color peppers, which turn from purple, cream and yellow to red come autumn. Warning: These are screaming hot peppers. Be careful if you have children.
Don’t forget ornamental kale and cabbages—unless you live in a deer-infested area. The frilly plants are a deer’s version of fast food. Again, treat these plants like annuals. Yank them out when the edges get brown and raggedy.
Lettuces, meanwhile, can do double duty. Multicolored versions add brilliance to a fall garden, and they’re edible. “There are so many different colors of lettuce now,” says Scanzaroli, who has been planting vegetables as ornamentals in Longwood’s Idea Garden for years.
Page 2: Continue the Harvest
Lettuces are cool weather plants normally associated with spring. But September and October are also prime growing periods, Athey says. “Throw some seeds in the ground in the beginning of September and get a fall crop.”
Like lettuce, many vegetables grow well when the heat has passed. “It’s something we’ve been working on for the past couple of years, and it’s becoming more of interest to homeowners,” says Ann Mattingly, community gardens manager for the Delaware Center for Horticulture in Wilmington.
Mache, arugula, kale and collards can adorn your garden and table well into December. “Mache will grow all winter long,” Mattingly says. The exotic-sounding greens are easy to grow, which is interesting considering they’re highly prized in restaurants, she says.
Spinach will last into late fall. Beets, radishes, broccoli and cauliflower are other late-season options.
Because many garden centers don’t stock fall-growing veggies, you’ll have to start them from seed. Sow in late summer or early autumn. If you’ve started the seeds inside, wait until the heat has died down before introducing them to the garden.
Since you’re out there digging, plant onions in fall for an early spring harvest, Mattingly recommends. She tucks vegetables in and among perennials.
Page 3: Take Time to Plant
Now is the time to hit the sales on perennial plants, shrubs and trees. Consider trees and woody shrubs especially—maples, dogwoods, azaleas and rhododendrons—which can thrive when planted in September and October.
“They can settle and develop a good root system,” says Scanzaroli. “For the rest of the season, they’ll continue to grow roots and establish themselves. Roots love cool weather.”
Consider plants that offer both spring and fall interest. Athey suggests Virginia Sweet Spire, a 4-foot-high shrub that holds its scarlet foliage until Christmas, furnishing a stunning backdrop for an early snow. Fothergilla—also called fothergill—goes through a “rainbow” of colors, she says, and it emits a honey-like scent in spring.
Remember, the root ball is the main reservoir for the tree or shrub. A dry winter necessitates frequent watering to keep plants from drying out, losing leaves and dying.
Plant spring bulbs in October and into November, suggests Jen Bruhler, parks and forestry outreach manager for the Delaware Center for Horticulture. Consider your design. You can put them in beds or even in the yard, since grass usually grows slowly when the bulbs are in bloom.
Hand-held bulb planters work well in a soft garden bed. For a turf bed, you may need an electric auger. In either location, you can also dig a hole and toss a grouping of bulbs in the space. While the planting depth varies depending on the bulb, it’s generally twice the height of the bulb. Carefully read the directions to make sure.
It can be challenging to remember where you planted the bulbs. And since last year’s foliage is long gone, it’s easy to dig up existing bulbs. Athey has a friend who tosses grape hyacinth into each mix. Since the plants keep their foliage most of the summer, they act as flags. A digital camera also makes it a breeze to record plantings.
Page 4: Put Your Yard to Bed
Many plants have a better chance of making it through winter if you mulch in fall. “Give the garden something to do over winter,” Bruhler says.
You don’t need to buy heavy bags of prepared mix. Run over leaves with a lawnmower and add the chopped bits to the garden. “Fork it in a little bit to keep it in place, because sometimes the wind will blow it out of place,” Scanzaroli says.
Be careful when you cut back dead stalks and branches. Many plants develop new growth on what looks like dead wood, and certain plants, such as the butterfly bush, should be cut back in spring, not fall. Remove seeds from flower heads and scatter them in desirable areas for next year.
Don’t forget the yard. Aerate, fertilize and seed it. The roots relish cooler weather.
When leaves fall and plants fade, assess the garden’s “bones,” Scanzaroli says. Look at the shrubs, trees and woody plants to determine if they’re properly outlining the garden and adding texture.
When your fall plants start to fade, fill containers with a mix of gourds. Come winter, replace the gourds with evergreens. Then grab your gardening magazines, cuddle up next to the fire and start planning.
Spring, after all, is just around the corner.