Woody plants have larger root systems than most annuals and perennials, and some special considerations should be made for growing them in containers. Follow these guidelines to keep your trees and shrubs happy year-round. See container design updates to make for a year-long display.
Choose your container and plants wisely
- Select a container two to three times the size of the root ball of your woody plant. Make sure it has enough depth for the root ball’s growth and plenty of room for your herbaceous plants.
- Use a frost-proof container, such as one made from resin, fiberglass, or stone, and make sure it has drainage holes.
- Consider raising the container off the ground, using feet to provide maximum drainage and air circulation.
- Choose plants that are two or three zones colder than the hardiness zone for your winter design.
Provide regular maintenance
- Choose good potting soil.
- Fertilize your container regularly throughout the growing season, but stop in fall to avoid promoting tender new growth.
- Check your container’s moisture level every day. Water when dry.
- Lightly prune trees or shrubs by taking off diseased, damaged, or dead plant material, but refrain from pruning the main leader of a tree.
Prepare for winter
- Be sure to water your container well going into winter.
- Relocate your container to a spot in the shade, which will help protect it from thawing out as
often during freeze-and-thaw cycles.
- Use an anti-desiccant on evergreens in a windy location to protect the leaves from drying out.
Transplant when needed
- As your tree or shrub grows, control its growth by root pruning and moving it into a larger container. During late winter dormancy, lift the woody from the container. Taking a sharp knife, cut off roots from the side and bottom of the root ball, making sure not to remove more than a third of the roots.
- After a few years of growing your woody in a container, transplant it into the ground.
Caitilin Driscoll has been a horticulturist for twenty-five years. She’s currently a landscape designer and the perennial manager for Shakespeare’s Garden, a nursery in Brookfield, Connecticut.