Quck answer
Trimming an overgrown arborvitae is a simple process that can help restore its shape and promote healthy growth. Start by removing any dead or diseased branches, making clean cuts near the base. Next, prune back any branches that are overcrowding or crossing each other, aiming to maintain a balanced and open structure. Avoid cutting into the bare wood as much as possible, as this can lead to unsightly gaps. Finally, remember to step back and assess the tree’s overall shape as you go, making adjustments as needed. Regular trimming will keep your arborvitae looking neat and well-maintained.
Arborvitaes (​Thuja​ spp.) are conifers that only grow from new growth. This means that trimming won’t promote new growth. If you prune too much growth, your tree could end up permanently damaged or could even die. Don’t let this prevent you from making cuts to keep the plants looking neat. Plan before you cut and take your time to avoid over-pruning these beautiful evergreen trees.
Timing for Pruning
Prune healthy branches just before new growth appears, around the end of spring and beginning of summer. Don’t cut back more than one-third of healthy foliage in a season and avoid cutting more than a foot from any branch at a time.
Technique for Pruning
When cutting a branch, avoid cutting it back too far or it won’t grow back. Cut off only the green portions of the branch, as the brown portions are old wood that can’t generate new growth. Scratch the bark to check if the wood is green. Work in small sections to avoid damaging the tree’s appearance. Trim vertical branches that shade lower parts of the tree and branches in the middle to allow more sunlight to enter and improve air circulation. This can help keep trees healthier and reduce disease risk.
Trimming Dead, Damaged, and Diseased Branches
Trim off damaged, diseased, dead, or errant branches as needed. This can reduce the risk of disease to the rest of the tree. When removing whole branches, cut them off as close to the trunk as possible. Remove the ends of diseased branches just below the dead needles and keep cutting until there is green growth again. Severely diseased branches may need to be removed entirely. Discard diseased branches in the trash and keep them away from healthy plants.
Using the Right Tools
Use hand pruning shears for smaller branches under 1/2 inch thick, lopping shears for branches 1/2 to 1 inch thick, and a pruning or bow saw for any branches over 1 inch thick. Keep your tools sharp to leave behind clean cuts, as ripped and torn branches are more likely to become diseased. Sterilize tools before and after pruning by wiping or dipping the blades in 70 percent or greater isopropyl or ethanol alcohol.
FAQ
1. How do I know if my arborvitae is overgrown?
If your arborvitae is blocking windows, encroaching on walkways, or touching utility lines, it is likely overgrown. Additionally, if the branches are drooping or the foliage is sparse towards the bottom, it may need trimming.
2. When is the best time to trim an overgrown arborvitae?
The best time to trim an overgrown arborvitae is in early spring before new growth appears. This allows the plant to recover and fill in any gaps during the growing season. Avoid trimming in late fall or winter as it may cause damage or stress to the tree.
3. What tools do I need to trim an overgrown arborvitae?
You will need a pair of sharp pruning shears or loppers for smaller branches, and a pruning saw for thicker branches. Make sure the tools are clean and properly sharpened to ensure clean cuts and minimize damage to the tree.
4. How much can I trim off an overgrown arborvitae?
When trimming an overgrown arborvitae, it is recommended to remove a maximum of one-third of the overall foliage. Removing more than that can stress the tree and affect its health. Focus on selectively removing the tallest and longest branches to maintain a natural shape.
5. How do I properly trim an overgrown arborvitae?
Start by removing any dead or damaged branches. Then, trim the longest branches back to a lateral branch or node. Make clean cuts at a slight angle to promote healing. Avoid cutting into the main trunk or removing too much foliage from the interior of the tree. Step back frequently to ensure you are maintaining a balanced and natural shape.