My enthusiasm for gardening wanes by autumn, and I long for the respite winter offers. While putting the garden to bed in the fall isn’t as much fun as watching it wake up in the spring, don’t let your care for the garden disappear just yet. “The end of October is really the first day of spring, because everything you do in fall sets up your success or lack thereof for the next year,” says John Kempf, CEO of Advancing Eco Agriculture and owner of a community-supported agriculture farm near Cleveland.
When it comes to putting the garden to bed, the first step should be to clean up your plants—including your food crop beds and any landscape plants you may have. First, prevent disease from returning to next year’s garden by removing any diseased plant material and disposing of it by burning it or putting it in the trash. Certain plants are more likely to harbor diseases, therefore it’s recommended to remove all vegetation from them. These include tomatoes, potatoes, raspberry canes and any plants with evidence of powdery mildew.
However, in healthy plants not on this list, it may be advantageous to leave vegetation on the plant. “Research has demonstrated that there is a better survival rate when foliage is left on,” says Francois Medion, farm manager for Duluth Grill, a local and organic food restaurant in Duluth, Minnesota. “It’s also the winter refuge of beneficial insects.”
Leaving most perennial foliage and flower stalks in place also provides winter interest, wildlife food and habitat, natural mulch and insulation, says landscape designer Betsy Danielson of Dazzle Gardens in Sandstone, Minnesota. Some plants prove particularly beneficial for wildlife and insects: Duluth Master Gardener Donna Peterson leaves the hollow stems of swamp milkweed as nesting material for bees; rosarian Kathy Ahlgren begins the winterization process the first week of August when she stops deadheading and fertilizing her roses. “By stopping deadheading, I’m allowing rose hips to form, which will trigger dormancy and add winter interest and food for the birds,” she says.
When cool weather hits, it’s also the time to bring in any houseplants that you may have moved outside for the summer season. Most of my houseplants spend their summers out on our deck. In the fall, I give them all a good bath with organic insecticidal soap before bringing them back indoors. I also quarantine them for a couple of weeks to make sure they are free of pests.
A mantra of the serious gardener is never to leave bare soil. One of the simplest techniques for making sure soil is protected and enriched is using mulch. “Mulch creates a great environment for the development of soil biology,” Kempf says. “When we mulch the soil, we get good levels of biological activity, nutrient availability and aggressive plant growth the following spring.”
Mulch is a blanket that protects plant crowns and roots from the extreme temperature fluctuations of winter. One of the best mulches is a good snow cover, but even very cold regions occasionally have winters with little snow. Thus it is important to mulch with plant material that does not compact and retains a certain degree of “fluffiness.” Chopped leaves work well, as do straw and marsh grass.
Danielson spreads a two-inch layer of compost or other organic material (shredded leaves or well-rotted manure) over garden beds and around woody plants. “Don’t dig or till it in. This is called no-till,” she says. “Just let it decompose over the winter, which will add a lush layer of nutrients, organic matter and worm-rich humus.”
Employ Cover Crops
Cover crops are an excellent way to maintain and enhance soil health throughout the winter. Several options for cover crops exist; choosing the right one for you depends on your crops, climate and other factors (read more about cover crops at Using Cover Crops in Your Garden). In his Minnesota garden, Jesse Davis, a market farmer from Grand Rapids, Minnesota, tills old plant material, raked leaves and mulching straw into his gardens after the first killing frost and sows winter rye into the beds in early October. “The small root growth helps with winter wind erosion and spring rain erosion,” he says. “The rye also emits a natural ‘herbicide’ through its roots to stifle competition. The rye herbicide needs about two weeks to break down in the soil, so we till it in two weeks before planting.”
Davis also plants Dutch white clover between rows in the spring. “If the roots of produce can touch the nitrogen-producing nodules of this legume, they can actually take it up,” he says. “It also can spread over the summer around the plants and create a sort of living mulch.”
Plan For Next Year’s Success
Fall is the perfect time to study your plantings so you can plan additions and rearrangements. I walk around with my tape recorder and list the plants I want to divide for spring plant sales or move to a better location next season. I transcribe the tape so I have a written reminder in the spring. Some gardeners stroll through their landscape with a video camera commenting on changes they’d like to institute the following year. You could also simply jot notes with pencil and paper.
Kent Lorentzen, a market gardener from Jacobson, Minnesota, tries to determine which varieties did best, how things sold and what was most worthwhile to grow. “I look at production, flavor, how easy it is to grow, how hard it is to weed, how difficult it is to pick, what it costs to grow, what the returns are, and most important, customer acceptance,” he says. “It helps to make notes for next year while things are fresh in my mind.”
Once outdoor fall chores are completed, come inside with a warm mug and a blanket to read new garden catalogs and dream about your next successful growing season.
Learn more about preparing your garden for winter in How to Winterize Tender Landscape Plants for Next Season.
Trimming Landscaping Plants
Use these tips to ensure a healthy spring for the following landscaping plants.
Bearded iris: Good fall housekeeping is essential to avoid invasion of the iris borer. Starting in late summer, keep all dead leaves and debris away from the base of the plant to prevent moths from laying the eggs that will hatch into borers the following spring. Cut leaves down to within 2 inches of the rhizome in late October and cover them with straw, evergreen boughs or marsh hay to prevent breaking of the shallow roots by winter thawing and refreezing.
Clematis: Wait to prune clematis until spring, when the emergence of new growth identifies the extent of winter dieback.
Evergreens: Don’t prune evergreens, especially arborvitae, in the fall.
Hostas: Remove all foliage to eliminate an area for slugs to overwinter.
Lilacs, azaleas, rhododendron: Don’t cut back lilacs, azaleas or rhododendrons in the fall, or you’ll remove flower buds that will open in the spring.
Peonies: Peonies are best cut back in the fall so new stems can grow unhindered in the spring.
Spirea and potentilla: Trim spirea and potentilla in the fall, removing the largest stems to the ground and trimming to shape and promote spring growth.
Sedums: Don’t cut back sedums until new growth has begun.
• Plant spring-flowering bulbs before the first frost.
• Divide/move spring-blooming perennials if you wish.
• Dig, dry and store summer-flowering bulbs such as dahlias, tuberous begonias and gladiolus to replant in spring.
• Clean garden beds of any diseased plant material, and amend with compost and manure.
• Leave plants with vines, seed heads or tall plumes for visual interest and wildlife habitat.
• Mark still-living plants with stakes or draw a map for future reference.
• Prune deciduous shrubs such as spirea and potentilla to promote spring growth.
• After a hard frost, cut to the ground any perennials that are diseased or that you don’t want to self-seed.
• Mulch all uncovered soil with leaves, straw or hay.
• Bring in houseplants that spent summer outdoors, but quarantine them for a couple of weeks inside.
• Keep trees, shrubs and evergreens well-hydrated until the ground freezes.
• Wrap the trunks of newly planted and thin-barked trees (such as apple, cherry, honey locust, linden, maple and plum) with hardware cloth to protect against winter sunscald and rodent damage.
• Empty clay and concrete pots, birdbaths and other items, and store them in the garage or basement to prevent damage.
• Let hoses drain before circling and hanging for winter.
• Perform a soil test. Kits are available at most county extension offices.
Margaret Haapoja is a freelance writer living on Little Sand Lake near Grand Rapids, Minnesota. She is the recipient of a “Life Award” from the Minnesota State Horticultural Society, and an award-winning garden writer.