So you thought the gardening year was over now that leaves have fallen, days are short and nights are cold?
Only if you want it to be.
“There’s always something to do in the garden,” said Julie Janoski, Plant Clinic manager at the Morton Arboretum in Lisle. “Any time you want a reason to be outdoors, all through the winter, there are things you can do to help your plants survive and prepare for next year’s growth.”
Here are some winter gardening tasks to keep in mind.
Prune shrubs and small trees
Winter, when deciduous plants are bare and dormant, is a fine time to trim and shape your shrubs. “With the leaves gone, you can see the structure of the plant better,” Janoski said. Plan to get the work done before the middle of March. You can prune any shrub during the winter, although if you prune branches from plants that bloom in spring, such as forsythia or flowering quince, you’ll be removing flower buds and you will forgo some blooms.
Have large trees pruned
Winter is the best time to have professionals prune trees that are too large to trim yourself. “Some trees, such as oaks, should only be pruned in winter,” Janoski said, to prevent the transmission of potentially deadly diseases. Working on frozen ground makes it easier for tree crews to avoid damaging the other plants in your yard with foot traffic and equipment.
Decorate the house with greenery
It’s easy and festive to include evergreen plants from your yard in holiday decor. “Just be sure that when you cut your greens, you don’t disfigure the plant,” Janoski said.
Pot bulbs for forcing
If some spring-flowering bulbs such as tulips and daffodils are left unplanted after the ground has frozen, you can still pot them in moist potting mix. Keep the pots in a sheltered place where they will get cold but not freeze, such as an unheated garage. “Bulbs won’t bloom in spring unless they have gone through at least four months of cold weather,” she said. In early spring, you can bring the pots indoors and start watering them to encourage them to bloom indoors. Or you can set the pots out in sunny garden spots to add color to the spring garden.
Spruce up
As winter weather takes its toll, perennials and shrubs may start to look a bit battered. “You can trim them back any time,” Janoski said. Perennial stalks may harbor valuable overwintering insects, so instead of removing them from garden beds, snip them into pieces and let them fall to the soil.
Replenish mulch
“If you notice spots of bare soil in the middle of winter, it’s still worthwhile to spread mulch,” she said. That’s because one of the major purposes of mulch in the Midwest is to keep soil from warming up too soon in late-winter warm spells, so plants’ roots stay cool and they don’t come out of dormancy and sprout prematurely. Spread mulch in an even layer, about 3 inches deep around trees and shrubs and 1 to 2 inches deep in perennial beds.
Water evergreens in warm spells
Plants that stay green in the winter never become entirely dormant. “Since their leaves are still at work, they still need water,” Janoski said. If the soil around them isn’t entirely frozen, it’s worthwhile to water. “You can use buckets if your hose is put away,” she said.
Plan
Winter is the time to prepare for next year. Use your notes and photos from last year to decide what changes you want to make starting in March: shrubs or trees you’d like to plant, places where you’d like to see more color, vegetable beds you’d like to add.
“Gardening is more successful if it’s well thought out,” Janoski said. “Do research and get advice to make sure you are choosing the right plants and the right design for you and for your space. Even if the weather is raging or freezing outdoors, you can be working on the garden from your computer or bookshelf.”
For tree and plant advice, contact the Plant Clinic at the Morton Arboretum (630-719-2424, mortonarb.org/plant-clinic, or plantclinic@mortonarb.org). Beth Botts is a staff writer at the Arboretum.
