Keep Plants Safe in Winter and Happy in Spring

When autumn nights start to get cold, it’s time to prepare your garden for winter. Winterizing not only makes your garden look better during the cold weather months, but will make for easier work in the spring and will protect less hardy plants from the cold. Start closing your garden down when there is frost in the forecast or the temperature consistently starts to drop to the low 40’s or mid-30’s (Fahrenheit), usually around late October or November.

Seven Steps for Preparing a Garden for Winter

Step 1.
Fall is Time for Evaluating Your Year in Gardening

Before you start your preparations, take a moment to review what worked and did not work in your garden over the past season. Fall is an ideal time to move plants (or remove plants) if you feel that they are not working in their current location. Fall is also a great time to plant bulbs, as well as plant bare-root shrubs and trees. It’s a good time, too, for dividing perennials. Division not only maintains the health of your perennials, but it’s also an easy way to propagate your plants so that you’ll have more coverage next season.

Finally, take a look around to see if your garden is lacking in fall blooms. If so, you may want to plan on planting some late flowering plants in the spring, such as Rudbeckia (Black-Eyed Susan), Aster Novi-Belgii, Anemone Japonica, Sedum spectabile. Hydrangea paniculata also provides nice color in the fall, but you don’t have to wait until next spring to plant them. Many hardier shrubs like panicle hydrangea are perfectly happy with a late planting and will use the extra winter to build up a bigger root system; it’s like getting almost another year into your plant.

While this applies to many plants, not all will appreciate that head start. Panicle hydrangeas are fine, but their big leaved cousins, H. macrophylla are not going to do well over that first winter if you’re popping them in around October. I’d wait until spring to plant them and any other plant that has the rep for being a touch tender (You know, I’d even wait until spring with hybrid tea roses, softer perennials, even azaleas and rhodies in those hardest hit areas). My rule of thumb is if it’s a plant that everyone says, “You can’t kill that thing”, it’s o.k. to plant it. If even one person says “I had some of those but I lost them that last bad winter”, let them go until spring.

Step 2:
Garden Clean Up

Start your clean-up by removing weeds and spent annuals from your beds. For shrubs and trees, remove diseased leaves, but pruning is not recommended in the fall as it may stimulate new growth just as the harsh winter is bearing down. Non-hardy bulbs, such as cannas, dahlias, and gladiolus, should be removed from the ground. Let the bulbs dry out in the sun for a few hours before storing them in a cool, dry place for the winter, such as a garage, attic, or basement.

Finally, if you don’t already have a compost bin, I urge you to consider starting one at this time. You can throw your cuttings as well as dried leaves in your compost bin, which will break down into a nutrient-rich compost for next season. Don’t throw weeds or diseased cuttings into your compost, however, as this will only multiply these problems down the road.

Step 3:
Winterizing Your Shrubs and Trees

Much of our suburban landscape is trees and shrubs. Fall is a great time to have your tree person come over to look at the topside of the landscape; the leaves are off and all is revealed, including any dying or diseased wood that should be removed. Sure, it’s one more thing, but when that big old branch drops and snaps your prized Chinese tree peony in half you’ll wish you’d done it. Limbing up our trees lightens the shade some the next season as well, so think about places in the garden that would benefit from that (If you don’t do it at all the shade just gets heavier year after year…).

Another key point to winterizing is to look to those evergreen plants that make up so much of the American landscape. Wind can dehydrate these perpetually verdant types and send them into permanent dormancy, so we should protect them somehow. The old school method is to hammer in three or four stakes around the plant and then take a few turns with a roll of burlap to make a windscreen. Not too pretty but very effective, especially if you stuff the top of the screen with straw or pine boughs.

The new method is to spray your plants with an anti-desiccant like Wilt-Pruf, creating a waxy coating on the leaves and needles to seal in the moisture. These sprays work great while they’re on, but it’s my experience that they usually need reapplying right around the time the nastiest storms of January and February are hitting, so remember to stock up for that second application (and don’t forget the mittens, scarf, boots…)

Often you hear recommendations about mulching up around trees and shrubs before winter hits, but I have seen much more damage from rodents (who move into these cushy, warm piles to spend the winter snacking on the bark and phloem of the tree you’re trying to protect) than any winter damage so I’m not a big fan of that theory (If it’s a rose or a turkey fig or something that really needs that extra protection, don’t bury it in mulch , use soil. A better job of insulation from both cold and pests…).

Step 4:
Cutting Back Perennials

Many perennials should be cut back to about 6 to 8 inches above the ground. A word of caution, however, regarding cutting back: Some perennials actually look quite attractive during the winter. If you’re not sure, you might want to leave them be and see if you like the way they look in your garden over the winter. Additionally, seed heads of some perennials (such as Rudbeckia (Black-Eyed Susan), Echinacea, Achillea, and Buddleia) are quite attractive and provide food for birds during the winter. Evergreen and alpine perennials (such as Artemisia, Dianthus, Heliantheum, and Heuchera) should also not be cut-back in the fall. Many perennials, however, look tired and messy during the cold weather months, so you’ll want to cut them back in the fall to keep your garden looking tidy and to avoid extra work in the spring. Prime examples of perennials to cut back are Alchemilla, Campanula, Coreopsis, Delphinium, Geranium, Hosta, and Veronica.

Step 5:
Mulch Creates Winter Plant Protection

Mulching for the winter protects plants from drastic temperature changes in the soil, insulating plants against extreme cold, and also prevents soil erosion. Don’t mulch too early, though, as it may encourage disease and pests. It is best to wait until after the first frost when the ground starts to freeze. In general, 4 to 6 inches of mulch, such as dried leaves, pine needles, shredded bark, or pine boughs, will provide an adequate layer of protection for your softer plants. If it’s a good hardy perennial I don’t mulch it; one less thing to do in spring. Using plants sure to be hardy in your area cuts down on the work you have to do; remember, don’t garden hard, garden smart! For plants in containers, the safest bet is to move them indoors. If your containers are too large or heavy to move, however, you can insulate the container by wrapping the sides in bubble-wrap and cover the soil with a generous layer of mulch.

Step 6:
Watering Prepares Plants for Winter

It’s a good idea to water your garden thoroughly before the ground freezes. Even with snow, winter can be very dry and harsh for many trees and shrubs, such as evergreens and rhododendrons, so it’s best to provide them with a large supply of moisture before the extreme winter weather arrives.

Step 7:
Clean and Store Your Garden Tools

Once your cleaning and cutting is done, it’s time to give some love and care to your tools. Clean, oil, and sharpen your tools, then store them in a dry place for the winter. Drain garden hoses and store them coiled in a sheltered place where they won’t freeze and crack. It’s a little extra work, but come spring, you’ll be delighted to pull out your tools that are ready to go to work with no fuss or muss.

Of course, if you choose to ignore winter preparations, the world will not come to an end, but you risk losing some of your less hardy or younger plants to severe cold, and also face a more daunting garden preparation chore in the spring. It’s well worth spending some extra time in your garden on a crisp autumn day to snugly tuck-in your garden in before winter takes hold.