Betty Montgomery: Pruning plants is important
February is a very busy time for me in the garden. Where I live, we have gotten more rain than normal and I have not been able to do as much pruning as usual so on the pretty days, I have had to do extra work to get it done. Pruning can give you a healthier plant as well as improving the looks. It is often a task most people are afraid to tackle, but it is needed occasionally.
Pruning plants at the right time of the year can be a key factor in your success. Pruning during dormancy is a good common practice, especially if you are doing major pruning. In the late winter, the sap is down and this is the ideal time to prune trees before the new growth starts to emerge in early spring. Pruning requirements of trees will not only vary according to species but also depending on the reason for pruning.
It is very important to know two things before you start. Know why you want to prune a particular plant and understand the natural habit or shape of the tree. If you are pruning to reshape a tree and major cuts are needed, do this in late winter. However, if this is a spring-flowering tree, if you prune much now, you will be cutting off the blooms for this next season. Sometimes you will have to sacrifice a year of blooms to accomplish your goal.
If you want to prune conifers, this too will vary depending on the species. Needled evergreens are best pruned in the late winter. Arborvitae, thujas and yews (taxus and cephlotaxus) should be pruned in the spring and early summer.
No pruning should be done on any plant in the late summer because the plant could put out new growth at the end of the season, causing the tree or shrub not to shut down as it normally does this time of year. The tender new growth that comes after pruning could be damaged and might even kill the plant.
Rules for pruning trees
1. Encourage a single trunk in most trees. There are some trees like crepe myrtles, river birches, and Japanese maples that are the exception to this rule. Ideally, trees should be pruned to have a single trunk because it makes a stronger tree and it is less likely to break with ice, snow or wind. Some trees will have a large amount of sap flow from the cuts. Birches, walnuts and maples are trees that come to mind. Do not worry about this. It is natural.
2. Never prune more than one-third of a tree’s crown in a season.
3. If you are cutting a large limb, make a number of cuts, starting at the end away from the trunk using a pole saw. Remember: “Do not bite off more than you can chew.” If it is a major job, it is best to hire an expert. Heavy limbs can fall in a different direction than you might think. These limbs are very heavy and could hit you and kill you.
4. When making small branch cuts, cut the branch back to a bud to encourage branching at that point. Remove crossing branches and branches that are growing back toward the center of the tree.
5. Make sure your tools are sharp and in good repair.
If you want to prune shrubs, know when it blooms. If they flower in the spring, prune immediately after they bloom. This way you will not cut off the buds that are developing for the next year’s flowers. Certain plants form buds shortly after flowering. Azaleas and mophead hydrangeas are two examples that you must prune just after they flower.
If you have a late summer or fall blooming shrub, prune these in the late winter or early spring. Buddleias and paniculata hydrangeas (ex. Limelight) are two examples of this rule.
Broadleaf shrubs respond well from being pruned a little from time to time to renew their growth. Azaleas, camellias, abelia, nandina are a few of the ones that do well with a little shaping and renewal.
When pruning, first remove dead, diseased or injured branches. Then prune the shrub making cuts inside the plant where the leaves will cover the cuts. With many shrubs, it is important to go inside the shrub and thin out some branches. This will let more air movement inside the plant, which is helpful to its health. Thinning out boxwoods is a good example of a shrub that likes to have a little “air” inside the plant.
Shrubs often need renewal pruning. People all too often purchase a home and plant shrubbery near the foundation of the house. Plants often become too large and out of proportion with the house. Here, some renewal pruning will not only help the plant look better but will also keep them in the right scale and set off the look of the house.
Sometimes the plants need to be pruned severely. Do this in late winter. After this is done and new growth starts to emerge, cut the tips of the new growth to encourage lateral branching. Many plants respond nicely to renewal pruning but some narrow-leaf evergreens might not like severe pruning. Pines, junipers, taxus and cedars would be better off being moved than too much pruning.
Many people are scared to prune, concerned they might not do it right. Just remember you can cut a little, look at what you have done for a few days and go back and cut some more. This way, you will build your confidence and will do it right. And if you do make a mistake and cut too much, it will grow back in time. Plants can be forgiving.
Betty Montgomery is a master gardener and author of “Hydrangeas: How To Grow, Cultivate & Enjoy,” and “A Four-Season Southern Garden.” She can be reached at firstname.lastname@example.org.