Keeping roses in pots provides advantages in garden design and maintenance. When placed on casters, containers are easy to move into a prominent position or into the spot that offers the most sun as the season progresses. A container also helps with maintaining roses, because a large one can eliminate the need to bend to deadhead spent blooms, remove diseased foliage and keep the soil clear of debris, all essential tasks for healthy, long-blooming roses.
When choosing a rose for a container, stick to cultivars that are compact and resistant to disease. Climbers and large shrub roses are best kept to garden beds and borders. Miniature roses and ground-covering types are good choices for containers. If the container will remain outside year-round, pick a rose that is rated winter hardy at least one USDA Zone lower than yours. (For instance, in Zone 6, use a rose hardy to Zone 5 or colder.)
Watering and Feeding
Growing roses in containers does require a bit more diligence when it comes to watering and fertilizing.
Keep in mind that containers dry out more quickly than garden beds. Also, the smaller the container, the more quickly the potting mix will dry. Check potted roses every day to see if they need water. When the growing medium feels at about a one inch depth, it needs a thorough soaking.
The extra watering that containerized roses require washes nutrients out of the potting mix, so the plant may need feeding every two weeks, or even weekly, with a dilute solution of liquid fertilizer. Adding a granular slow-release fertilizer at the start of the growing season is also recommended.
Repotting
As the rose plant grows, increase the size of the container, or simply prune both the plant and its roots to maintain a smaller size. (Trim roots by removing the plant from the pot.) Refresh potting soil every few years—this is a good chance to root-prune, too!
Winter Protection
Where frost and freezing temperatures occur, protect potted roses in a garden shed or basement, especially if the container is not freeze-proof. (This is more about protecting the pot than the plant.) If garden space allows, plant the roses, container and all, in the garden and top-dress with mulch to keep both rose and container safe.
Image courtesy of Proven Winners