One of the garden trends we’re hearing about for 2014 is the greater use of woody plants — shrubs and trees — in containers. Using woody plants in containers offers greater choices to those with small or patio gardens. It also gives gardeners an opportunity to try plants that may be outside of our hardiness zone. And, a dramatic arrangement of containers with shrubs or trees can create a big impact in the garden.
However, container plants do require some special care and considerations.
Container. If you are planting a shrub or tree in a container, be sure to select a pot that is large enough to accommodate the plant’s roots as they grow and big enough to balance the larger size of the plant.
Planting. Choose a container planting mix for the pot. Fill the bottom of the container with a layer of rock, crushed pottery or crushed plastic pots to encourage drainage. Then add potting mix to about half full and add some slow-release fertilizer. Plants in containers need more nutrition than those in the ground. Remove the shrub or tree from its nursery pot and tease the roots. If the roots are circling the pot, make a few cuts about a half inch deep around the rootball to encourage growth. Place the plant in the pot and fill it with more potting mix. Tamp it lightly and water well. Here’s a video that demonstrates the process well.
Care. Place the pot in the appropriate sun situation (sun, part sun, etc.) and keep in well watered. A container will need more water than a garden in the ground. According to this bulletin from Cornell University, a container needs 3 gallons of water per week on average. In June when growth is strong or during hot weather, it may need even more.
What next? If the shrub or tree is hardy to our zone, you can remove it from the container and plant it in the ground in the fall, watering it well, if you would like. Overwintering trees and shrubs in containers is possible, either by heeling them in outdoors, if they are zone hardy, or storing them in a protected environment. Even figs can be grown in the North with the proper protection.
What to plant? There are many options for trees and shrubs that grow well in containers. Hydrangeas, boxwood, rhododendrons, even Japanese maples would be good options for container growth. Here are some suggestions from plant wholesaler Proven Winners.