Stop Making “Mulching Volcanos”
A layer of mulch around your trees helps protect them from mower blades and prevents soil from drying out. But piling it up like a volcano around your tree traps moisture against the trunk, which can cause rot. Additionally, when mulch is too deep, it prevents tree roots from getting the oxygen they need. “Always mulch out and not up,” says Daniel S. Bauer, an arborist, and president of Arbor Equity Inc. He recommends using hardwood mulch, which will slowly break down and provide some nutrients to the soil. Just keep your mulch layer to a depth of 2–3 inches.
Don’t Use Pruning Paint
Pruning your trees and shrubs promote the plants’ health, but skip the pruning paint. You may have seen products that say they help seal the cuts left behind, but actually, they seal in fungi and bacteria that can cause disease. They also make it harder for trees to seal off their wounds naturally. Plus, most tree wound sealers are petroleum-based, which isn’t great for living tissue. “Would you use it to treat a cut on your own skin?” asks Linda Chalker-Scott, a professor and horticulturist at Washington State University. “If the idea repels you, carry that feeling over to plant health care,” she advises.
Avoid Topping Your Trees
A too-tall tree can cause problems with electrical lines, or it might be outgrowing its space. However, reducing a tree’s size by indiscriminately lopping off large branches, referred to as ’topping,’ is not a good way of caring for trees. This can stress out the plant enough to kill it and exposes it to disease, decay, and damage from the sun or insects. In addition, any smaller branches that grow in to fill the space left by topping are more likely to break during storms. Properly and safely pruning large trees away from power lines is best done by a trained arborist. And if a tree no longer fits the location, it’s better to remove it entirely and plant a better variety for the site, Bauer says.
Quit Staking Young Trees
Newly planted saplings occasionally need help standing up straight, but in most cases, staking is unnecessary. Trees need to move and sway in the breeze to help them grow strong roots and trunks, and lashing the trunk to a stake or wire prevents that natural movement. “When the stakes are removed (if they ever are), the lack of trunk and root development makes these trees prime candidates for breakage or blow-down,” Chalker-Scott says. If you must stake in a high-wind area, that’s okay, but set a calendar reminder to remove stakes or guy wires six months after installing. Staking too long, too high, and too tight are leading causes of tree damage. Most importantly, don’t skip the love and attention, says Bauer, who points out that trees are not “set it and forget it” plants. With regular watering, careful pruning, and taking measures to prevent insect damage, your trees will thrive for decades.