Many perennials can live for years in a container garden. Once you've found the perfect arrangement of these plants for each container, you can devote your gardening budget to other garden areas, knowing the containers will thrive with a minimum of care.
Gardeners worry about the root system of the container surviving the harsh temperatures of winter because they don't have the insulation perennials planted in the soil do. If the plant can grow in a USDA Hardiness Zone that is two zones colder than your area, they can not only survive but can thrive.
Choose the Right Container
Keep the winter temperatures that your container garden is subjected to when choosing the container for your container garden. Terracotta doesn't survive cold temperatures, and a cracked container defeats the purpose of the garden that comes back year after year. Some glazed pottery may survive cold temperatures, but fiberglass, heavy plastic, stone iron or lead will have the best chance. Make sure that there is a drainage hole in the bottom of the container that you choose.
The Soil Matters
Start the container garden out right by using the proper soil. Look for a soil mix that is prepared specifically for containers. These potting soils will give the container garden the drainage that your plants need during the winter as well as during the growing season.
Winter winds can be drying to the container garden. Keep winter container gardens looking lush all year long. Conifers and broadleaf evergreens are especially susceptible to the drying winter winds and will benefit from an application of antidesiccant to keep them from drying out.
Feeding the container plant encourages new growth. Stop feeding the container garden about seven weeks before the first expected frost in your area. This will prevent damage to the tender new growth that will affect the plant. Resume your fertilizing routine in the spring when the container garden starts growing again.
Watering the Winter Garden
Plants in the container garden can't absorb moisture from the frozen soil. Once the container has frozen, it's time to stop watering the container plants. But until then, continue to water.