How to Winterize a Garden: Ready Your Plants to Weather the Cold With These Expert Tips

As fall winds down, you’ll pull sweaters out of storage and crank the thermostat, but what about your outdoor plants? Knowing how to winterize a garden is key to welcoming spring with an abundance of thriving greenery—as opposed to a sad brown patch of lawn. If frost, snow, rain, and freezing temperatures are in the forecast, know that your outdoor spaces don’t have to face the elements without a little assistance.What materials are needed to winterize a garden?To prepare your garden for winter, you’ll need burlap; straw; garden tools like pruning shears and a pruning saw or lopper; a compost pile or ready source of nutrient-rich matter; and, ideally, some winter-ready plants that can take the place of flowering annuals and edible plants.One more item to add to your list (in potentially large quantities): mulch. “One of the biggest things we do is mulch, and then mulch some more,” says Christina Stembel, founder and CEO of D2C e-commerce flower company Farmgirl Flowers. “We bring in what feels like an absurd amount of mulch every fall and use it just about everywhere. It helps insulate roots, suppress weeds, protect the soil through rain [and snow], and eventually adds organic matter back into the ground. We mulch our garden roses, peonies, perennial beds, [and more].”How else can I prepare to winterize my garden?Amy Enfield, who has more than 30 years of experience in the lawn- and garden-care industry and a PhD in Plant and Environment Sciences from Clemson University, offers thoughts on a mindful first step ahead of digging in: “Before pulling out tools or buying materials, walk your garden and take stock of what you have. Note which plants are annuals that will not return, which are perennials you want to protect, where the soil looks tired or compacted, and which areas might benefit from a cover crop over winter. This assessment keeps you from doing more work than necessary or missing something important.”Burlap adds a layer of protection against the elements for this outdoor plant in the wintertime. Photo: Erman Gunes/Getty imagesHow to winterize a gardenPull up foliage and apply proper covering materials“Do not begin with applying mulch,” says Jose Lopez, the founder and owner of Williams Landscaping Inc. “First, walk through your fall garden to pull up dead foliage. Pull any foliage that shows signs of disease as well. Next, apply appropriate care to the plants that will remain. Finally, cover your soil. If you do not complete these first three steps, you’re simply burying the problems of the growing season.” To cover that soil, there are three primary materials, each of which plays a different role, Lopez says. “Compost supplies nutrients to the soil. Mulch serves as insulation [and you can] use the leaves that are readily available, shredding them for mulch. Straw has no place in most flowerbeds but is suitable for vegetable gardening.” Just be mindful of where you are placing covering materials, and “do not layer large amounts of wet leaves over a newly planted shrub because the water can cause root rot at its base,” Lopez notes.Prepare raised beds for winterRaised garden beds tend to be used for annual flowers and edible plants, and these typically need to be removed, says Dr. Enfield. “Leaving their debris in the garden over winter creates a cozy habitat for overwintering pests and fungal disease.” Pull any spent annuals and finished vegetable plants, disposing of or composting them. “Diseased plant material should go in the trash rather than the compost pile,” Dr. Enfield says.Once the beds are cleared, Dr. Enfield says to “amend the soil before it freezes. Working organic matter, like compost, composted manure, or a bagged soil into garden beds in fall gives it the entire winter to work into the soil structure, so it is ready to support planting in spring. Spread three inches over cleared beds and work it into the top six inches of native soil before winter sets in.”Prepare perennials for winterSome plants are tough enough to make it through the winter without much support, but others can benefit from some TLC in the autumn. For those plants that aren’t hardy enough to withstand winter in your climate, you’ll need to break out some of the aforementioned materials: burlap, straw, frost cloth, and horticultural fleece. Amanda Webb, head gardener at Windy Hill Farm and Preserve, notes that “burlap is particularly useful for protecting exposed evergreens from winter wind, while straw can provide insulation around the crowns of marginally hardy perennials. I prefer breathable materials over plastic, which can trap moisture and create problems when temperatures fluctuate.”Shrubs and other borderline hardy plants also need to take cover from the cold. “Some plants, particularly broadleaf evergreens like rhododendrons, hollies, and boxwoods, as well as any shrubs or perennials that are on the edge of their cold hardiness zone, benefit from physical protection over winter,” says Dr. Enfield. Burlap is the most commonly used material for this purpose; it can be wrapped loosely around individual plants or used to construct a simple windscreen that protects evergreens from the desiccating winter winds and sun, which can cause browning and leaf scorch even in plants that are otherwise cold-hardy. “Avoid wrapping plants in plastic, which traps moisture and heat and can do more harm than good. Burlap breathes, which is what makes it the material of choice.” For young or newly planted trees, wrapping the trunk with tree wrap or burlap protects against sun scald, “which is the cracking of bark caused by rapid temperature changes on the south and southwest sides of the trunk during winter thaws.”Frost protection will help shield these potted plants from freezing temperatures. Photo: Coolpicture/Getty ImagesAdd cold-weather plantsGardening doesn’t have to stop in winter; you just have to focus on plants that thrive in the cold. “I can’t stand seeing a vegetable bed sitting bare all winter,” says Mirela Bajic, senior garden designer at House Designer. “If you’re not growing anything in it, put something in for the soil’s sake. Winter rye is brilliant for that, [as] the roots hold everything together through the bad weather and then you just cut it back come spring.” She adds that many plants are more than rugged enough to make it through frosty, even snowy seasons. “Kale, cabbage, leeks, chard, [and more] all keep going through the cold if you let them.” Winter-ready crops like these help hold the soil together, provide some lovely greenery amid the gray backdrop of wintertime, and can even be used in hearty cold-weather meals.Look beyond just succulents and cactiHow to winterize sprinkler systemsIt’s imperative that you tend to your property’s sprinkler systems and hoses, says Webb. “Drain irrigation systems and hoses if freezing temperatures are expected,” she says, or you risk catastrophic damage once water in the lines freezes and expands.First, you’ll need to shut off the water supply to your sprinklers and hoses, removing the latter and putting them away for winter. Then, blow out sprinkler lines using compressed air to expel any residual water from the pipes. You should use a compressor set to 80 PSI or lower to avoid damaging sprinkler heads in the process. Once the lines are clear, leave the water shut off at the source inside your home (or garage or greenhouse or wherever the main water connection point is found) while leaving external valves partially open so last drips can fall and trapped water has a place to expand if it freezes.Tips on how to make your neighbors green with plant envyMove your gardening indoors for winterJust because it’s too cold outside to grow colorful flowers or tasty tomatoes, peppers, or herbs doesn’t mean you can’t keep the growing going on indoors, and no dedicated greenhouse is needed, either. With a self-watering hydroponic growing system like a Gardyn Studio 2, you can grow full-sized plants indoors, including the same flowers and edible plants you’d place in a raised garden bed outdoors. If indoor space is at a premium, you can also use a smaller countertop system like a LetPot that can be used with a smaller number of flowers or food plants.Frequently asked questionsHow do I make my own mulch?All those leaves you painstakingly rake or blow into a pile need not be bagged up and sent off to the dump; you can recycle it all to make your own mulch, which can preserve and nurture your garden throughout the winter. It’s best to use a leaf shredder to break down fallen leaves into smaller bits, rather than simply spreading collected leaves out atop your beds. You can also use a lawn mower to break down leaves, though this will dull the blade with extended use. If you have a wood chipper, you can use branches and brambles to make mulch as well. Even grass clippings can make great mulch, provided you dry it in the sun first and mix it with some thicker material, like those shredded leaves or chipped branches.Looking for farm-to-table freshness? Get growing on your own at-home harvest in four simple stepsDo I have to remove all the dead flowers to prepare my garden for winter?You don’t have to remove every dead flower, be it a truly finished annual or a dormant perennial, says Stembel, of Farmgirl Flowers. “One thing I’m trying to get better at is not cleaning everything up just because it looks messy. There are flowers that went from stunning to eyesores everywhere, seed heads, and so many perennials that are better off being left alone for a while so the foliage can die back naturally and the plants can store energy for next year. A lot of those seed heads and stems also feed birds and give beneficial insects places to overwinter.” Sometimes, the best thing you can do to winterize your garden is to leave it alone.When should you plant bulbs for spring flowers?You should plant bulbs in the autumn when soil temperatures are consistently holding at around 55 to 60 degrees Fahrenheit, and about six weeks before you expect the first frost. “[It’s] my absolute favorite fall ‘chore,’ planting the bulbs,” says Stembel. “This fall we’re planting thousands of daffodils, tulips, and drumstick alliums around the farm. I know thousands sounds excessive [but] bulbs might be my favorite kind of delayed gratification. By spring, I’ll mostly have forgotten that we trudged outside on cold, rainy fall days and dug what felt like endless trenches to plant all of them until the little green sprouts start popping through the soil. Those first flowers bring us so much joy right when we need it most [after] months of cold, gray weather. In fall, I wonder why we planted so many, but by spring I’ll wonder why we didn’t plant more.”