When to prune a particular shrub can be a confusing practice for even the most experienced gardener. Luckily there are many plant guides to help remind us of pruning times or even a quick call to your local Extension office.
Now that we finally remember the best time to prune azaleas or French hydrangeas, the nursery throws us a loop with everblooming plants. Although not new, the Encore® series of azaleas and Endless Summer® collection of hydrangeas have the wonderful characteristic of blooming repeatedly throughout the growing season. When is the best time for pruning these repeat blooming shrubs?
In general, if you select your Encore® azalea carefully, it should need very little pruning. There are many sizes available to fit every space. Reduce your need for pruning by choosing a selection that will not outgrow your space. For example, Autumn Sangria® is a larger selection to at least 4-5 feet tall while Autumn Embers® is about 3 feet tall. If your plant needs a little selective pruning, the best time to prune is still after the first initial big bloom in April.
Encore Sangria has vivid pink flowers. Photo by Beth Bolles, UF IFAS Extension Escambia County.
Pruning time for Endless Summer is the same for other mophead hydrangeas even though it blooms on both old and new wood. You may selectively prune after the first bloom. It is always fine to deadhead faded blooms back to the first healthy buds.
Many shrubs can benefit from a little pruning. Choosing what to prune to maintain a plant’s natural look can sometimes be a challenge. Get a few tips on pruning shrubs with cane type growth from UF IFAS Extension Escambia County.
Not all fall color is a good thing. This statement is especially true when it comes to twig pruners and twig girdlers. These two species of longhorned beetles can certainly disappoint your grand expectations of a beautiful array of fall color. Both species cause the tips of twigs to fall to the ground in late summer, sometimes leaving your trees in an undesirable form.
Twig Pruners
The twig pruner (Elaphidionoides villosus or Anelaphus villosus) is a small longhorned beetle that attacks numerous species of hardwoods. It is usually classified as a secondary pest of declining trees and shrubs. Female twig pruners lay their eggs in late spring at the leaf axils. When the eggs hatch, the grubs bore into twigs and continue to bore as they mature. The larvae then chew concentric rings just underneath the bark. The infested twigs and branches eventually drop to the ground with the larvae inside. The larvae pupate inside the fallen twig throughout the winter.
An adult twig pruner. Photo Credit: University of Georgia
Twig Girdlers
The twig girdler (Oncideres cingulata) is a small longhorned beetle that invades many species of hardwoods. Female twig girdlers lay their eggs in late summer in small twigs (about 3/8 inch diameter) that are covered with a thin layer of bark. The female chews a concentric ring around the outside of the twig, causing the end of the twig to die. The female chews a small notch in the dead twig and lays her eggs. After the eggs hatch, the larvae feed on the dead twigs and develop into adults before chewing their way out. The adults fly away to new host trees.
An adult twig girdler. Photo Credit: Lacy L. Hyche, Auburn University
Management and Control
It’s important to plant the right plant in the right place. Healthy trees and shrubs are the best defense against insect pests. Twig pruners and twig girdlers live in dying or dead twigs and branches. If you have trees that have suffered damage from these pests you will notice an abundance of fallen twig ends around the base of your trees. Rake and remove fallen twigs from around the trees and destroy or dispose them. This will help reduce pruner and girdler numbers in subsequent years.
Recently, I spent some time with my uncle at his home in Perry, Florida. Perry specifically and Taylor County as a whole were one of the hardest-hit areas from Hurricane Idalia. My uncle said that most of the powerline poles had been replaced in his and surrounding neighborhoods as a result of this storm. Some were still being replaced when I was there. Every home in the area had large amounts of tree debris cut and piled up along the streets for pickup. Most every pile had the remains of large pine trunks intermingled in the debris.
Tree debris along street following Hurricane Idalia in Perry, Credit Larry Williams
The only damage to my uncle’s home was from a neighbor’s large pine tree. The top of that tree was blown through the air and slammed into his roof, puncturing the roof and leaving a large hole through the bottom of the garage ceiling. In addition to the direct wind damage and resulting downed trees, with a storm such as Idalia, there will be much follow up removal and pruning of leaning, partly uprooted, and damaged trees.
Trees are an important part of our ecosystem, economy, landscape and heritage here in North Florida. As a matter of fact, Taylor County began a Pine Tree Festival in 1955 to help educate the public about the timber industry in that area. Now known as the Florida Forest Festival, the goal of the festival is to promote the benefits of our state’s forests as well as to celebrate people who protect and work in them. The 68th Annual Florida Forest Festival is scheduled to take place in Perry on October 28, 2023. Here is a link with more information on the festival: https://floridaforestfestival.org.
It is important to not wait until a storm event such as Idalia to inspect and manage trees on your property. An ounce of prevention is worth a pound of cure when preventing tree damage. Even without a major storm, we have relatively high winds associated with our frequent thunderstorms here in Florida. Compared to many parts of the United States, we live in a fairly high-risk area for storm damage with lots of large trees.
Professional help sometimes is your best option when dealing with trees. Property damage could be reduced by having a professional arborist evaluate unhealthy, injured or questionable trees to assess risk and treat problems.
Hiring a certified arborist can be a worthwhile investment. To find a certified arborist in your area, contact the International Society of Arboriculture at 888-472-8733 or at www.isa-arbor.com. In addition, here is a UF/IFAS Extension link with a wealth of information related to trees and hurricanes: https://hort.ifas.ufl.edu/treesandhurricanes.
Anyone can prune but not everyone prunes correctly. In order to prune correctly, you need to understand how plants respond to pruning.
When a pruning cut is made on a stem or limb, new growth will develop just a few inches below the cut. This is because of a hormone that is produced in the terminal bud (the bud at the end of a branch or twig). This hormone prevents dormant buds located directly below the terminal bud from growing. So, when you routinely shear plants, a lot of dense, new growth will be produced near the outer portions of the plant. This eventually results in less light reaching the interior portions of the plant, foliage within the canopy becomes sparse and the plant appears stemmy or hollow.
Thinning generally is a better method of pruning most shrubs. Thinning is cutting branches back to a lateral branch, a lateral bud or the main trunk. Basically, a thinning cut is the complete removal of a branch or stem for the purpose of thinning or opening up the plant. Thinning encourages new growth within the interior portions of the plant, reduces size and provides a fuller, more natural looking plant compared to plants that are routinely sheared.
Keep in mind the desired results when pruning. If you plant a row of shrubs that will serve as a hedge or screen, begin pruning them the same year that you plant. Many times, people wait several years before pruning a newly planted hedge Doing so can result in little growth at the base of the plants, which means a privacy hedge that can be seen through. Because of the fact that new growth on plants only occurs a few inches below the cut, you should begin pruning early to encourage a compact growth habit.
Pruning time varies among plants. Plants that are not grown for their showy flowers such as holly, boxwood and privet can be pruned during late winter, spring and summer months. Avoid pruning during fall or early winter because the new, tender growth produced as a result of pruning will be subject to cold injury.
Plants that bloom before May such as azaleas, forsythia, spirea and climbing roses should be pruned shortly after they bloom. It is best to avoid pruning plants in this category later than July because they set flower buds in the fall.
Plants that bloom after May such as crape myrtle, gardenia, bush roses and abelia can be pruned just prior to spring growth in late February or early March.
Avoid severely pruning junipers, cedar, arborvitae and other narrow-leaf evergreen plants because it may cause them to die outright.
