It’s much harder overwintering potted plants. If you fail, try, try again. How to Overwinter a Plant Others may require storing of their bulbs inside through the winter. 2. However, as the temperature continues to drop, their roots might die unless they are protected. Place your container into your hole atop the gravel, then spread a layer of garden soil over the top of the pot. If your plant is not currently in a container that can withstand frozen temperatures, consider repotting it before continuing. If the soil is dry more than an inch deep, water lightly but don’t soak the soil. Since plants in pots effectively have their entirety exposed to the elements, roots and all, they tend to freeze easier then plants that are planted in the ground. and for good reason: the same rules just don’t apply. When spring comes, lift your potted plant from the soil as soon as the ground thaws and new growth begins to appear (you don't want a buried plant to soak in water from spring rain any longer than necessary). Watering containers with needled and broadleaf evergreens such as hollies, boxwoods and ivy is essential in winter. Follow these easy steps to learn to safeguard your container plants and ensure they make it through winter healthy and unscathed. Dig a hole that's slightly deeper than the container you wish to bury, allowing for just a bit of extra room around the edges of the container as well. Depending on their hardiness, some potted plants will respond to the first frost by going dormant just like garden plants do. The key is to have an indoor spot with plenty of light. Just the sheer number of pots is a challenge to manage. Therefore, you would want a plant that is hardy to zone 3 or 4 if you plan to overwinter it outdoors in a pot. For example, if the standard recommendation is to mulch over a particular garden perennial for winter, do so with the buried potted plant. Woody Plants and herbaceous perennials should be completely dormant or hardened off before covering for the winter. How to Overwinter Dahlias. 1. Why You Should Overwinter Perennials in Containers Even if you picked perennials that are hardy to your zone, perennials in containers are subject to harsher winter conditions than … However, many perennial plants such as roses, peonies, and hibiscus can also be grown outdoors in containers and kept alive through winter. Small potted fruit trees that spend the summer on a deck or patio can also live indoors for winter. Managing Garden Pots Before Winter. If they are in containers, I move the containers under cover. Constant moisture can cause plant … Welcome to the World of Container Gardening, Making Herb and Vegetable Container Gardens, Troubleshooting Cultural Disease and Insect Problems, Constructing and Caring for Container Water Gardens, University of Illinois at Urbana-Champaign. Look for a spot that will stay in the range of 32 to 45 degrees Fahrenheit. Storing dormant plants is one of the oldest and most time-honored practices of overwintering geraniums, and it’s fairly simply to do. You’ll start by digging up the geraniums in your yard, roots and all. This works best if you’d like to plant a new tree in spring. Many berry shrubs don’t need much water while dormant, but check containers at least once a month. Doing so with moderate the temperature swings and increase the likelihood of your perennials surviving the winter. There, they'll be protected from any winds that can rapidly drop temperatures and will enjoy some heat radiation from the house. That being said, protecting your potted plants throughout the cold winter is not always easy—even species that are technically cold-hardy in your area may experience harsh conditions they can't tolerate and many species that survive the winter just fine when planted in the ground can die in containers without the proper care. For example, a gardener in zone 5 can expect perennials rated for zone 3 or colder to survive the winter in containers. While some plants can survive light frosts, others will die for good as soon as their cells freeze. Depending on where you live in central Illinois, we are zone 5 or 6. Alternatively, you can keep them in an enclosed area, such as your garage or basement. Some plants need to go through a dormancy period and will need to be overwintered in a cool, dark space such as a garage or basement. Give Them a Drink. Spreading a layer of gravel at the base of your hole will facilitate drainage in the spring as the soil in the pot eventually thaws. Before getting pots ready to overwinter, make sure the plants inside are well watered, and check throughout the winter. To raise the humidity around your plants, group them together, or keep them near the kitchen sink or in a steamy bathroom. According to Climate Container Bulbs in Cold Climates… Winter-flowering pansy. Overwintering Potted Plants By Shila Patel | September 1, 2001 Fortunate are gardeners in mild-winter regions, where container gardening is a year-round pleasure without the threat of shattered pots and frozen plants familiar to many of us. At the end of each season before winter comes, the cleanup becomes a burden. Mulch it … Cut Stem. If I run out of room for storing pots (which seems likely), I can also store the tubers in the same manner I store dahlias, after cutting the stems back to 6 inches or so. Plan to winterize your buried container plant just as you would any similar plant growing in the ground. What to do? If the container is large and able to withstand the elements, and if the plant is at least one zone hardier than your area (i.e., if you live in Zone 5, herbaceous perennials in containers need to be hardy to Zone 4 or lower), the likelihood of successfully overwintering the plant in its pot outdoors is high. How to Overwinter Potted Ferns. The key to overwintering plants in containers is to prevent the soil mass from freezing and to maintain moisture in the soil throughout the winter. However, perennials that require winter dieback and a dormancy period shouldn't be brought inside. Three steps to overwinter berries in containers and get them ready for spring. Shake them off outdoors to get rid of any excess dirt. This makes it difficult to say exactly how to overwinter … Ideally, the rim of the pot should be slightly lower than the surrounding ground, allowing you to cover it completely without creating a lump in the surface of your garden. Thus, it's typically best to position plants in a location where the temperature swings will be less dramatic. Cluster several potted plants together in a sheltered part of your property, such as against a house wall. 1. Depending on the size of the growing container larger pots can usually remain outside but do keep an eye on them. Plants to Overwinter. It didn’t cover hardy bulbs (tulips, daffodils, hyacinths, crocuses, garlic, etc.) If these hardy succulents are planted in the garden, I generally leave them over winter and just clean up the brown leaves or transplant them in the spring. Winter-flowering pansies with yellow, maroon, white or purple ‘faces’ will … If you can provide shelter to help insulate your container plants from temperature swings, your potted perennials will stand a much better chance of survival. Freezing can be prevented by having a large soil mass in a well-insulated container or planter located in a protected area. If you need to, mark the top of the soil so you know where to find your plant come spring. However, many perennial plants such as roses, peonies, and hibiscus can also be grown outdoors in containers and kept alive through winter. You can use a cool vaporizer, too, or sit pots on trays or saucers filled with pebbles and some water. As such, cold hardiness of the selected rose cultivars is key. The small amount in pots tend to give up heat more readily. If covered with snow, plants will get plenty of moisture. Make sure your container is strong enough to last through winter. Cut a 4 to 6 inch portion of a green stem just above a node (the part of a stem from which … All other planters and containers should be emptied of soil and plants and stored upside-down to prolong their useful life. Dahlias are summer-flowering plants that grow from tuberous roots. Learn tips for creating your most beautiful (and bountiful) garden ever. Overwintering outside in pots of most any kind will likely result in the entire contents of the pot freezing through and ultimately resulting in significant cold injury or the death of the plants during the coldest months. Freezing can be prevented by having a large soil mass in a well-insulated container or planter located in a protected area. This will keep the mums foliage tight and close, and allow the timing of the blooms for fall and not late summer. In addition to clustering your plants together, you can also cover the pots with a tarp, straw, or another insulating material. The key to overwintering plants in containers is to prevent the soil mass from freezing and to maintain moisture in the soil throughout the winter. Whatever measures you take to protect your potted perennials for winter should be put into action a week or so before the first frost is expected. If you apply that simple rule, you eliminate most of the problems of overwintering plants in pots. Introducing "One Thing": A New Video Series, The Spruce Gardening & Plant Care Review Board, The Spruce Renovations and Repair Review Board, Insulating materials (such as mulch, straw, or leaves). I personally don’t usually over-winter the original geraniums but take cuttings, again, rooting six or more in one wide pot in the house and then separating them into new pots in April. Large concrete and wooden planters are typically able to withstand northern Illinois winters without being cleaned out. Move the pot back to the location where it resides for the warmer months. And if the ferns are Boston Ferns, warmer temps are better for them as well. Plastic containers are usually resilient enough to tolerate freezing, while certain natural pot materials, such as untreated terra cotta, readily absorb water, which can expand when frozen and end up cracking the pot. There are several ways to do this. The general rule of keeping plants in pots two zones different than the zone you live in helps. Cathy Askia is a Master Gardener and member of The Spruce Gardening and Plant Care Review Board with over 30 years of home gardening experience. I end up with plants like these in my bathroom, laundry room and guest room. ... Over-wintering plants is difficult - even nurseries and greenhouses lose plants during the winter months, but that is all part of gardening. The more porous a container is, the more likely it will be to crack. Choose a relatively sheltered location in your garden or elsewhere on your lawn to house your plants for winter. Choose a spot that is relatively shady—contrary to the belief that sunny is best, placing your potted perennial in a bright location can exacerbate any thaw-freeze cycle over the winter. For plants that have been in containers all summer, water thoroughly and give it the recommended fertilizer rate. This container plant can easily be saved for life again on the porch next year. Overwintering Mums Indoors For Spring Bring plants indoors, pots and all, once the first hard frost hits. Additionally, indoor conditions are often very dry in the winter, and many perennials need humidity—if your house lacks moisture, invest in a humidifier if you plan to bring any container plants indoors. Knowing the plant’s needs is the key to keeping plants over winter successfully. You will simply have to do more than leave the pot … Canna lilies are one of the easiest tropical plants for the gardener to overwinter – which is exceptionally convenient as they are also one of the most versatile plants in the summer garden. Herbaceous perennials should be potted up by late September or early October to allow them to become established for several weeks before cold temperatures arrive in late November. To do so, use chicken wire and stakes to form an enclosure around the plant, filling the silo with loose leaves or straw to help keep your plan cozy. Poorly established and pot-bound plants tend to overwinter poorly. It's not necessarily low temperatures that kill plants over the winter, but rather the rapid swings between warmer and cooler temperatures that can stress the plant by thawing and freezing it. This may also involve spreading leaves, straw, or compost over the spot where you've buried the pot. Storing your plants in a semi-dormant state is a gentler way to overwinter them, so it's a good option for younger plants that haven't had as much time to develop a strong root system. I find this method is unreliable—some years the geraniums do fine, other years they don’t—but it’s not a bad choice if… As a general rule of thumb, a perennial plant should be rated for two hardiness zones colder than your climate to be dependably hardy in a container for winter. Lavender plants that are hardy for your climate can overwinter pretty well on their own in their container as long as it is not sitting under a pile of snow, tree leaves or ice.