If you love growing plants in the summer, you probably have at least a few that are in containers. Whether they’re on your porch, in the garden, or sitting on your patio, you need to take special care to protect your container plants through the winter. Here are some tips that should help you plan for your container plants, so you can enjoy them again next year.
1. Put Them in the Ground
Yes, you put those plants in containers for a reason. But if you have perennials that are going to be left outside over the winter, it’s always best to plant them…even if you do so while they’re still in the pot. Not being in the ground gives the roots very little protection from the cold. If you can find a somewhat sheltered area near your house or fence, that may be even better. No matter what spot you choose, put down a thick layer of mulch (2 to 4 inches) after the ground freezes.
2. Consider Your Zone
Most plants can survive over the winter in their containers (without planting) if they are rated for growth at least 2 USDA Hardiness Zones lower than where you live. So if you’re zone 6, plants rated for zones 4 or lower should be fine.
3. Get Strong Containers
If you can’t put your perennials in the ground, make sure your plants are in strong enough containers to withstand the cold, wet weather. Porous materials often have a difficult time surviving the winter, and if your pots don’t survive, neither will your plants. If your pots are terra-cotta, for example, they can absorb moisture and then freeze, which could crack your pot.
4. Cluster Your Pots
If you won’t be planting them, take your container plants and put them close together in a place right next to your home which offers some protection and warmth, such as a south facing wall. You can even pile leaves or other material around them for extra protection.
5. Put Them in a Cold Frame
You can build a cold frame or simple greenhouse-type cover for your potted plants to help protect them. If you go this route, keep an eye on them. It could actually get too warm in there, and you don’t want the temperature going over about 40 degrees. If it gets too warm, lift the cover during the day and replace it at night.