Overwintering Container Plants: Preparing Potted Plants For Winter

Potted Plant On A Windowsill Overlooking A Snowy Background
(Image credit: Andrey Nikitin)

Freezing temperatures, gusty winds and dry winter conditions can adversely affect your potted outdoor plants. Container plants in winter need tender loving care to see them through until the balmy spring season. A few steps and tricks will provide protection for container plants in winter. Container plantings give dimension and texture to the outdoor living space, but they need some extra help to withstand cold temperatures. Potted plants winter care is important because there is not much buffer between the roots and the outdoor temperatures, making roots more sensitive to cold than those in the ground. Begin preparations well before that first freeze or you may lose one of your prized plants.

Why Winter Care for Container Plants?

In addition to the fact that potted plants have exposed roots, container plants in winter also have the challenge of overly dry or overly wet soil. Water has a temperature above freezing and it actually gives off heat as part of the freezing process, which can help protect the roots. Overwatering, however, can cause the pot to break due to the expansion of the ice as it forms. Excessively wet plants also have a tendency to rot in confined spaces with too little drainage. Ensure the plant is in a container with drainage holes in well-draining medium. Pick off any dropped leaves on the surface of the soil to prevent fungal issues, like Boytris, which overwinter on foliage. Finally, the potted plants winter care moves to root zone defense.

Preparing Potted Plants for Winter

Plants that are deciduous or die back should have the tops cut back to the crown. Water well to prevent dessication and give moisture occasionally if the plants are in a dry area. Cluster pots together with the smallest on the center under an overhang, hedge or other protected area. If you have windows in your garage, you can store your container plants in an unheated garage. Similarly, an unheated greenhouse works great for overwintering container plants or even a hoophouse. Some plants do fine without a cover, but for really hard freezes, you may want to have a clear tarp available to tent over tender plants that are not inside some support structure. If you only have a colored tarp, make sure to uncover the plant during the warmest part of the day every couple of days to get light.

Alternate Method of Overwintering Container Plants

Most plants will overwinter nicely if planted in the ground. You literally insert the plant, pot and all, into a hole that covers it to the surface level. For added winter care for container plants, cover with leaf litter and mulch around the stems and trunks of the plants. Piles of pine mulch or straw are also excellent for preparing plants for winter. In some regions, rodent control will be necessary to prevent squirrels and rats from gnawing on the plants. There are also insulated thermal blankets you can purchase. Erect them over a frame to keep the plant from freezing and still allow some air and light inside. Pull the mulch away from plants in early spring so new shoots can see the sun.

Bonnie L. Grant

Bonnie Grant is a professional landscaper with a Certification in Urban Gardening. She has been gardening and writing for 15 years. A former professional chef, she has a passion for edible landscaping.