Here are some tips from the pros on keeping your trees in good shape:
“Anything that is not growing to its potential, not as fast, go ahead and push it” by fertilizing, extension agent Bob Neier said. Especially in its first four or five years, fertilizer will help push a tree along. But if it’s older and growing well, it doesn’t need fertilizer.
And if you’re always pruning a tree to keep it from outgrowing its space, don’t fertilize; that only pushes on more growth. Another consideration: Trees that are fertilized the most and put on the most growth tend to break up in storms, Neier said.
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Fertilize as trees are losing leaves and going dormant, usually in late October, he said. If you’re fertilizing the lawn under a tree, you’re fertilizing the tree already. If not, use a fertilizer labeled for trees.
Ward Upham of K-State writes in the Horticulture 2013 newsletter:
“Many parts of Kansas went through an extremely wet period during the first half of August. Remember that too much rain can be as damaging to root systems as too little. Roots need to breathe. Therefore, root systems that had already been damaged from the previous drought now may have suffered further damage. Therefore, we need to give these plants some extra care to give root systems a chance to recover.
“Watering is the most important practice to help a tree recover from stress. If your soil is getting dry, be sure to water your trees to a soil depth of 10 to 12 inches. You can check this with a metal rod or wooden dowel. It will stop when it hits dry soil.” In general, when the soil is not frozen, water trees planted in the last couple of years every week and all others every other week. Don’t keep trees constantly soaked, however. They will get root rot if the roots are drowning and can’t breathe.
One easy way to water trees is with a soaker hose, making it provide a more uniform watering by connecting it to a Y-adapter, Upham said. Use a female-to-female connector on the female end so that both the beginning and ending of the hose are connected to the Y-adapter. This will equalize pressure. It also is helpful if the Y-adapter has shut-off valves so the volume of flow can be controlled. Too high a flow rate can allow water to run off rather than soak in.
You may also want to include a backflow preventer, Upham said. Try to circle the tree with the soaker hose as far out as the outermost reach of the branches. On smaller trees, you may circle the tree several times with the hose.
A general rule for watering newly planted trees is 10 gallons of water a week. With sandy soil, split that into two 5-gallon applications. One way to measure: Drill a small hole near the base of a 5-gallon plastic bucket. Fill the bucket with water so that the trickle from the hole slowly moistens the soil. If the water starts running off rather than soaking in, plug the hole and come back later to water again.
Many people can handle doing light pruning of trees themselves, but if a branch is too high to easily reach from the ground or too big, it’s best to call a professional arborist to do the work. Don’t risk getting hurt.
Use a pruning saw for the thickest branches, loppers for midsize ones, and hand pruners for stems less than half an inch across.
But put those loppers down if you plan to do lots of cutting. Heavy pruning now encourages growth, and it’s too late in the season for that.
“Our general recommendation is it’s always a good thing to take dead branches out, and you can do that any time of the year,” Jason Griffin, director of the John C. Pair Horticultural Center in Haysville, said. “If you’re doing light pruning, you can do that most any time of year. Heavy, major reconstructive pruning requiring the work of a professional arborist, you might want to wait till things go dormant,” after fall color. At that point, “the days are so short it’s not going to encourage new growth till spring flush.”
Pruning in the dormant season can be done through February and into March, depending on the weather. You may want to wait until closer to spring, so that pruning cuts will heal more quickly.
Some reasons for pruning:
• To remove dead, damaged, weak, diseased or crossing limbs.
• To remove waterspouts.
• To encourage trees to develop their natural form and ornamental character. As a tree grows, you may want to remove some of the lower branches, but don't remove more than a quarter of them.
• To stimulate future flower and fruit development.
• To remove low-hanging, unsound, dangerous limbs or limbs that get in the way of sidewalks, curbs, signs, gutters or utility lines.
• To control density. You shouldn't prune to diminish height, only to open up a tree so the wind will move through it without tearing it up. If one branch shoots out above the rest, it can be brought into conformity with the rest.
• To remove suckers from the base of trees. If possible, these should be torn off, not cut. If the suckers are cut, they will return again and again.
• Other reasons: a limb is rubbing against the house, large limbs have broken, branches extend too far out, more light is wanted through the tree, the weight on the end of branches needs to be reduced so they don't break, and lower branches need to be removed so people can walk under them, or to give more light to plants underneath.
Weeping trees have different requirements. The branches of mulberries, for example, should be kept off the ground to keep insects from getting on them, to keep the branches from whipping the soil underneath and to allow things to grow under the tree.
If a tree is not flourishing, don’t prune live wood or leaves from the tree. It will need all the leaves it can get for energy.
When you prune, make clean cuts just outside the branch collar on the tree. The collar – the swollen area where the branch joins the trunk or a larger limb – must remain on the tree.
Hold the shears so that the upper blade is toward the part of the branch that will remain on the plant, advises Reader's Digest's “1001 Hints & Tips for Your Garden.” That way, any damage will occur on the pruned branch, not the one on the plant.
When hiring someone to prune, make sure he is licensed or certified. If such a person suggests “topping” a tree, find somebody else. Topping is the equivalent of butchering and is only used as a last resort. Even then, hire an arborist for the next two to three years to do corrective pruning.