August is an excellent month for pruning many shrubs and trees in the landscape, just ahead of the fall growth spurt. It's also a perfect time for pruning backyard fruit trees for size control. Removing excess growth now instead of waiting until January will help keep fruit trees smaller.
Summer is an excellent time for restorative pruning. Summer pruning tasks may include removing dead, damaged or diseased branches. Many people think of pruning as a winter task, but there are a number of great reasons to prune your trees and shrubs in summer.
So if you are wondering, is it ok to prune or trim trees in the summer, just know that pruning in the summer is primarily for shaping and creating a solid structure. Heavy pruning should be saved for winter, when trees are under less stress.
That's especially for oak and elm trees! If possible, you should not prune oak trees at all during the summer to reduce the chance of oak wilt, which is a potentially fatal disease, and do not prune elm trees at all during the summer to reduce the chance of Dutch elm disease, both of which are fatal diseases.
Avoid pruning during the blooming season (spring and summer) to preserve next year's bloom. Instead, prune in early spring or fall after it is at least three years old. Remove 50 to 75 percent of the top foliage to promote health and minimize diseases.
Helps Control Disease
Some trees, like oaks, should only be pruned during the dormant season because they are especially susceptible to oak wilt disease, which is known to spread extremely fast in the spring and summer.
April, May and June are not good months to prune because deciduous trees need to use their stored energy to produce new leaves instead of healing wounds. Also, pruning during warmer spring months encourages the spread of diseases such as Oak Wilt and damage by pests such as Emerald Ash Borer.
Few plants are pruned this time of year because pruning encourages new growth that does not have time to harden off before winter. Late-season pruning typically does more harm than good.
In summer, leaves engage in photosynthesis and produce carbohydrates. The tree translocates those carbohydrates throughout to grow roots, shoots, leaves, and fruit. By removing leaves during summer pruning you remove a resource point and thus reduce energy for overall tree growth or regrowth.
Generally, the best time to prune or trim trees and shrubs is during the winter months. From November through March, most trees are dormant which makes it the ideal time for the following reasons: Trees are less susceptible to insects or disease.
July is the month for pruning fruit trees, especially well-established ones. A few simple, well-placed cuts can improve fruiting and limit the size of the tree, ensuring it stays compact enough for a small garden.
The best time of year to cut down a tree would be during winter or early spring when the leaves have all fallen and the branches are free from them. You may worry that the frozen ground would make it more difficult to remove a tree, but the fact is, warm earth is more easily disturbed.
Municipalities and homeowners often remove the lower limbs for pedestrian and vehicular clearance or to let the sun shine in for grass to grow. Mature trees, especially evergreens, benefit when healthy lower branches are left intact. Removing large limbs can increase the risk of decay.
The approximate thermal death threshold for trees in a temperate zone is 115°F depending on its age, thermal mass, water tissue content, and the ability of the species to adjust. Optimum growing conditions for most trees range from 70°F to 85°F. Overall tree temperatures usually run around air temperature (+ or - 4°F).
Effects Of Heat Stress On Trees
Extreme heat can impact many functions of a tree. Looking at the leaves, photosynthesis is reduced, leaves may fall off, and the growth rate of the remaining leaves decreases. Concerning the whole tree, heat stress can slow overall growth.
Signs of Heat Stress in Trees
As the tree becomes more stressed, stems and branches can start to droop. Irregular yellowing of interior leaves or needles. Failure to produce healthy-looking new growth, making the tree canopy look sparse. Rust-colored spots or bumps on leaves.
Can tree branches grow back? When pruned properly, removed tree branches will not grow back. Instead, the tree will grow what looks like a callous over the pruning cut, which helps protect the tree from decay and infection. Because trees heal all on their own, you don't have to use a pruning sealer!
Don't Prune in Late Summer and Fall
Pruning shrubs in August or early September may encourage a late flush of growth. This new growth may not harden sufficiently before the arrival of cold weather and be susceptible to winter injury.
The best season to prune trees is while they are dormant, or generally between November and March. This means waiting for them to lose their foliage and cease growth, but before forming buds. For fruit trees such as the apple tree, prune in late winter.
Pruning during the growing season always stimulates new growth. During summer's heat, having to produce that ill-timed new flush of growth greatly stresses a tree. Pruning in the fall is even worse as it prevents the tree from going into a natural dormancy. The exception is heavily damaged, disease or dead wood.
ALWAYS prune back to or just above a growing point (branch or bud) or to the soil line. NEVER leave a stem or branch stub. NEVER top a tree to “rejuvenate” growth.
Cut too much and you'll risk nutritional deficiencies or branches that are too weak to tolerate the wind or fend off diseases or insect invasions. Over pruning and topping can permanently disfigure your trees, or even kill them. Further, a tree's foliage is important for protecting it against excessive sun exposure.
Proper pruning encourages strong growth, increases flower and fruit production, improves plant health, and removes damaged limbs, all which give aesthetic appeal to a tree. Pruning at the right time and in the right way is critical, since it is possible to kill a healthy tree through neglect or over-pruning.