Can You Plant Evergreen Shrubs in Pots?

Choosing a Shrub

• Smaller evergreen shrub varieties, or those that are easily trained to remain small, are the best choice for pot culture. Junipers provide a good choice for containers, notes Judy Scott of the Oregon State University Extension Service. These evergreens are tolerant of most conditions. You can prune them to maintain a certain shape or trim them lightly to maintain their size while allowing the trees to develop a natural shape. Another suitable container option is the boxwood. This broadleaf evergreen tolerates severe pruning but is less tolerant of the dry conditions that sometimes occur in a pot. Generally, any smaller evergreen variety with low nutrient and water needs can grow well in a container.

Container Considerations

• Heavy containers work best for potted evergreens because they anchor your shrubs and prevent them from blowing over on windy days. Clay pots are heavy enough, but they can crack in areas with cold winters. Wood is a suitable choice for both weight and winter durability, but the wood will eventually rot if not treated. Evergreens typically require repotting every two to three years, and you can replace the container when you repot. Use pots that are as wide as they are deep to ensure they remain steady and don't fall over, and to provide insulation for the root system, advises Scott. No matter what container you choose, it must have bottom drainage holes to allow excess moisture to drain out. If you must move your container, keep it on a wheeled cart to make moving less cumbersome.

Soil Needs

• The soil in the container must provide for all of the shrub's needs. Use a quality potting soil that contains compost and other organic amendments. Extension horticulturist Neil Bell warns against using soil directly from your garden when planting an evergreen shrub in a pot. Overly dense soil drains poorly, which can lead to root rot. A quality potting soil contains peat, vermiculite, perlite or other amendments that aid drainage. The shrub will also need regular fertilization because the nutrients first provided in the soil are used up quickly. A general-purpose, slow-release fertilizer or a feed formulated for the particular evergreen variety works well. Apply at the rate and frequency recommended on the label for your shrub and container size.

Basic Care

• Providing adequate water keeps the evergreen healthy in summer. Containers dry out quickly and may require daily watering, depending on how hot and dry the weather is. Evergreens only go semi-dormant in winter, so they require irrigation whenever the soil isn't frozen. The evergreen also requires annual pruning in early spring to maintain its size and shape. Quick-growing evergreens, such as boxwood, may require maintenance trims throughout summer. Pruning back the roots by a third when you repot will keep the evergreen shrub small enough for container culture, notes Bell. If your evergreen tree isn't winter hardy, move it into a greenhouse or an unheated garage during the winter. You can leave hardy evergreens outdoors in a protected area. Wrapping the tree with thin burlap helps prevent cold and wind damage to the branches, while wrapping the pot in plastic helps add further insulation to the soil, notes Don Janssen of the University of Nebraska-Lincoln Extension.