By Robyn Stewart, ANR Agent
Ornamental plants are those which are used in a landscape to primarily add visual appeal and decorative value to an area. In addition to this, they can be used for cut flowers and provide food and shelter to animals and insects. Pruning ornamental plants can do a number of things including maintaining a desired size or shape and promoting healthy growth and production. Sometimes, we may prune a plant to help reduce its size, limit competition for resources in a bed, or to help correct damage caused by insects, diseases, or other injuries. Each plant in a landscape has an individual growth habit and a different pruning requirement. Some may never require pruning and others will need frequent pruning. While anyone can prune a plant, many people do it incorrectly or at the wrong time of year, which can result in misshapen plants, reduced growth and flowering, or even the death of the plant.
How and when you should prune depends on the growth patterns of the plant in question. In order to flower in the spring, some plants set their buds in the fall. Pruning these plants during fall or winter will cause a reduced flower display come spring. These plants include azalea, dogwood, forsythia, redbud, and rhododendron. Plants that flower in the summer, on the other hand, can be pruned in the fall and winter with no impact on their growth. As a general rule, plants that flower before May should be pruned after they bloom, while those that flower after May can pruned just prior to spring growth.
There are a huge variety of pruning tools on the market at a variety of quality and price points. Most home pruning can be done with hand pruners, lopping shears, pruning saws, or hedge shears. Be sure to match your pruning tool to the appropriate size of plant you are working with. Hand pruners work best for branches under ½ an inch in diameter while lopping shears are better for anything larger than that. Make sure that you sharpen and oil your tools once a year to keep them in good working condition.
Once you have identified your plant and what time of year to prune, you will want to consider what type of pruning is appropriate. First, understand that the most vigorous new growth of a plant occurs within 6 to 8 inches of the pruning cut. Therefore, some general guidelines include the following. For shrubs, it is often better to thin the plant by cutting branches back to a main stem or trunk, rather than shearing the external branches into your desired shape. Thinning encourages new growth in the interior of the plant which makes the plant appear fuller. A second principle to keep in mind is to make your pruning cuts all the way back to a bud, branch or main stem. This helps the plant heal more quickly and prevents disease and insect infection. If your plants are completely overgrown or having some health issues, renewal pruning is a great way to manage them. This means cutting the plants back 6-12 inches above ground level. The best time to renewal prune is in mid-march when spring growth begins.
Each plant has specific needs when it comes to pruning, and the Extension Office is happy to provide information and guidance to you. If you need help determining what time to prune or what type of pruning is appropriate for you, let us know at uge3181@uga.edu or 706-359-3233.
