After a long summer spent toiling in our gardens under the hot sun, it’s tempting to welcome the cooler days of fall by hanging up our trowel and gloves, reeling in the hose, and taking a break from all the weeding, watering, and pruning that are such an important part of our warm weather routine. Still, spending a little extra time now to prepare perennial beds for winter will pay off come spring. A few easy steps are all it takes to make sure you’ll start the new growing season off right, with disease-free garden and plants that are ready to burst forth in color.
How to Divide Perennials
If you are planning to move or divide any of your spring and summer blooming perennials, fall is a good time to do this. The excessive heat of the summer months can be stressful on plants and makes adapting to changes more difficult. Starting at least six weeks before the ground freezes, dig up and divide perennials that have grown too large or have developed bare spots in the center. Dividing now will control the plant’s size and reinvigorate blooming next year. Place new plants in the ground in early fall. It will give them time to become established and “harden off” before the arrival of freezing weather.
Saving Bulbs
If you have tender bulbs such gladiolus, dahlia, or canna, dig them up now and store in a warm, dry place to prevent them from being killed off by cold winter temperatures. Wait until after their leaves start to shrivel and turn brown. Cut the tops off a few inches above the ground – you can use these tops as a makeshift handle. Using your spade, gently loosen the soil from around the bulbs. Be careful not to nick or slice them, and gently lift out of the ground. Lay the bulbs out to dry for several weeks on paper or a raised screen in the basement or garage, out of direct sunlight and freezing temperatures. Then label the bulbs and store for winter in containers layered with peat moss, shredded newspaper, sand, or sawdust.
Important of Water in the Fall
Continuing to water perennial beds on a weekly basis throughout the fall and right up until the ground freezes will help ensure you have plants with a strong, healthy root system. In spring, plants will rely on this root system to get them off to a good start. Watering deeply – at least an inch per week between periods of rainfall – is more conducive to optimal root health than shallow watering as it encourages roots to reach deep into the soil for hydration. If it is a dry autumn season, special attention should be paid to evergreens, particularly the broadleaf varieties like boxwoods, as they continue to lose water from their leaves throughout the winter, making them highly vulnerable to winter burn. Avoid using a high nitrogen fertilizer with perennial plants in late summer or early fall because it will drive above-ground growth that may not be adequately established to survive the first winter freeze. On the other hand, a slow-release fertilizer with lots of phosphorus and potassium is suggested as it will encourage root growth.
Remove Dead Plant Material
Weeding is another task that (unfortunately!) becomes no less important just because the mercury starts to dip. Going through perennial beds to remove weeds before winter sets in will prevent insects and diseases from hiding out and overwintering in the garden. Remove any dead material or plant debris that has collected in flowerbeds as well. In addition to minimizing the pest problems you encounter in spring, beginning with a tidy, weed-free landscape always feels like a welcome head start on the growing season in March and April when it’s time to grab the Wellies and start mucking about in the outdoors again – the equivalent of finishing all your homework the night before. It always feels good to be prepared!
The Advantage of Pruning Aggressively
Cutting your plants down to the ground before winter is another beneficial practice. Since they will grow back in spring from their root system, most perennial stalks and stems can be safely trimmed to just above the soil level as plants enter their period of winter dormancy. This is one more task that when completed will make for lighter work as the weather warms next spring. Feel free to allow for some exceptions though – leaving a few perennials standing can add winter interest to the landscape and seed heads will provide food for birds. Just remember to cut these plants back before the new growth starts to come up next year.
Don’t Forget the Mulch
Add mulch – pine needles, wood chips, chopped leaves or other organic matter – to your perennial beds once temperatures become steadily cooler and the ground is starting to freeze. Mulching will provide a protective layer of insulation to the soil throughout the winter months and prevent damage to roots from the freezing and thawing cycles of late winter and early spring. Spread the mulch two to three inches on the ground around plants, but take care to avoid covering them up completely or piling it on too thickly, which can result in a wet environment, fungus problems, and rotting plants.
Cover Vulnerable Plants
Some of my favorite shrubs just aren’t quite hardy enough to withstand our Midwestern winters without a little help. This knowledge comes from harsh lessons learned with certain varieties of roses and hydrangeas. These plants can be wrapped or covered for winter protection. Once temperatures are consistently cold, wrap the plants in burlap or landscape fabric. Another easy trick is to install a chicken wire “cage” around them, then fill it in with leaves raked up from your yard. Just make sure to remove any coverings in the event of unseasonably warm days, as you don’t want plants to become overheated.
Now It’s Time to Relax with a Cuppa
And now you can relax! Spend the next few months curled up with your seed catalogs, placing orders and making plans. By taking the time in autumn to prepare your garden for the bitter winds and cold months ahead you’ll be all set when the warmer days of early spring finally do roll around and it’s time to dig out our gloves and get out there again.
If you haven’t yet done it, now is the time to remove the stems of herbaceous peonies, cut down stalks of tall perennials like Phlox and Monarda, and shear the leaves from Siberian iris. You’ll thank yourself in the springtime when you’re trying to figure out what is planted where.
Is there a deadline for all of this activity? Not really. It’s really a matter of comfort—your comfort—while working outside. I’d rather wait until the insect population dies down and I don’t have to wear sunscreen, but it’s up to the gardener to think about what her garden needs are to get through the winter.
Predicting the Weather?
Winter in the Midwest comes down to lowest historical temperature. An important resource for any gardener is the United States Department of Agriculture’s Plant Hardiness Zone Map. This tells you how cold it has gotten over the past several years. To pinpoint your USDA Hardiness Zone, go to the interactive zone map site, a handy tool to help estimate how cold it could get. Another handy guide that uses historical data to predict with some accuracy when it will get nippy is the Old Farmer’s Almanac. It gives the potential first frost or light freeze date.
I found a great article on the National Oceanic and Atmospheric Administration (NOAA) website that gives probability of first snowfall based on your location. It’s based on records between 1981 and 2010. NOAA also offers a site for true weather geeks that gives the U.S. Climate Normals in the 30 years between 1981 and 2010.
Meanwhile, NOAA offers the following definitions of frost and freeze:
Bringing in The Hose
There are certain items we use throughout the summer that fall into the “support” category. These are the things we reach for constantly, the workhorses of the garden. Because of the location of my outdoor spigots and the size of my garden, I have a few hundred feet of hose. Bringing in the hose can be a conundrum in a year such as this. There are potted plants that are still blooming and therefore need an occasional drink of water. But leaving the hoses out in mid-November leads us down a slippery slope, not to mention a major tripping hazard.
When the trees dump their leaves in earnest, they hide a potential danger that lurks beneath them. These dangers include hose guides, elevation changes, and hoses. One year I had to shuffle through a six-inch layer of leaves in order to find where I’d neatly coiled 200 feet of hose in preparation for bringing it inside. I’d wisely wound it up after detaching it from the spigot, but was too tired to bring it in after wrestling it into submission on a cold morning that turned the pliable rubber into an unyielding, inflexible pipe.
In case you’re thinking of leaving the hose attached to the outdoor spigot through the winter months, don’t. While I always knew it was a bad thing to leave a hose attached in winter, I never knew why until I saw this video that explains it. It boils down to ice, and once it begins to form inside the hose, pressure builds, and the ice has nowhere to go, causing it to possibly crack a part of the indoor piping, flooding your basement or crawl space.
Cutting Requires Heavy-Duty Shears
Cutting a whole garden full of plants down is a tough job. “It’s a good thing it’s cold out,” I told myself as I gathered my sharpest shears. I kept my hand pruners on stand-by and went for the Fiskars long-handled hedge shears. When choosing a pair of shears, I go for lightweight, and start with the long-handled shears just to cut things down to a size I can manage. For some plants, like ornamental grass iris foliage, and most annuals, it’s all you need.
My cutting arsenal wouldn’t be complete without Bacho Long-handled Lawn Shears. These are the ones that come in for the close-to-the-ground cuts—peony stems, and anything with an upright demeanor. The handles on these shears are long enough to clip without bending, which makes them a back-saver.
For thicker branches, I love the Radius Pro Loppers (//radiusgarden.com/collections/cutting-tools/products/pro-lopper?variant=10824626753). They’re light in weight and make precise cuts close to the main stems of woody plants. And speaking of woody plants, don’t forget to wait until very late winter (between January and March) before pruning trees and shrubs. If you prune these plants too early in the fall, there is a chance they’ll form new growth that can be frozen. Besides, it’s really a lot easier to see what you’re doing once the leaves are gone.
Storing the Non-Cold Hardy
As desperate as we are for color in our winter landscape, it’s not a good idea to leave some of our ornaments outdoors to suffer the rigors of winter. Glass gazing globes and most clay pots should be brought indoors and out of harm’s way for the winter.
There are some planters that can get through the winter without damage. Containers made of fiberglass and plastic are pretty tough and can be left out—a good thing because they can get heavy with a full load of potting soil. Inexpensive plastic pots become brittle with age. I’ve coaxed an extra year out of them by dragging them in close to the house onto the concrete patio where they are covered by a deep overhang.
I don’t expect anything to survive in the planters I leave out for the winter. Plants I can’t do without I will dig up and store in the garage. I’ve collected several pineapple lilies (Eucomis) that are reportedly hardy to Zone 7. Since winters are unpredictable here at the southern tip of Lake Michigan, I bring them, pots and all into the garage, and place the pots on top of a sheet of Styrofoam to help insulate the root ball. The roots are what need to be protected, after all.
This summer, I experimented with breathable fabric pots in which I planted my Eucomis and other non-hardy plants that I wanted to save. I planted the Eucomis, fabric pot and all, in a large container, leaving the handles and about an inch of the top of the fabric above the soil line. This made it easy to pull the fabric containers out in the fall, and stack them loosely into a lightweight container that I lined on the inside with bubble wrap.
A Word (or two) About Mulching
Whether you make your own mulch by mowing up the fallen leaves, or buy it in bags, timing the task is important. Applying a thick layer of mulch over plants that are still actively growing in late fall tells their roots to keep on working. I consider Thanksgiving a good signal to mulch away. Of course, I have so many trees around my garden I don’t have to mulch, there are plants that require their own individual treatment.
If you don’t have the benefit of fallen leaves, you’ll want to check your coral bells (Heuchera), which are just waiting for an excuse to pop out of the ground. The phenomenon is called frost heave, and some plants are more susceptible than others. The best way to prevent heaving is to follow these guidelines:
One last thing to consider when trying to talk yourself out of dealing with the dead stems is how your garden will look in spring when the bulbs come up. Nothing detracts from a spring bulb display more than a bunch of dead stalks looming over the sprightly blossoms. You did remember to plant bulbs, right?
IF YOU’RE REALLY INTO WEATHER DATA:
The NOAA Regional Climate Center has a page from which you can extract historical last and first days that temps dipped below 32 degrees F. It’s not user friendly, so NOAA Weather Forecaster Julie Dian-Reed from the Ohio office gave me the parameters to use:
Single Station: First/Last Dates
Options Selection: YEAR RANGE: POR-2016 (this means Period of Record)
Criteria: Min Temp < 32
Period Beginning: July 1 (this keeps your requests near the ‘growing season’)
Station Selection: You need to narrow by the Chicago office. No- unfortunately it’s not alphabetical by city name, its alphabetical by office ID — Chicago’s ID is LOT