Summer pruning is best done in August-September, when the majority of branches have set a terminal bud. Note that when branches are actively growing, their tips feature a vegetative bud that continues to produce leaves and lengthen. This is visible—you see new leaves forming at the tip of a branch.
Summer is an excellent time for restorative pruning. You can correct problems that have resulted from over-pruning or poor pruning. You can also clean up damage from winter and spring storms. Proper pruning will begin to restore most plants' natural shape.
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 summer pruning reduces the barren and unproductive area and facilitates light penetration for excellent fruit quality and colour development. It diverts the energy into those parts which are capable of bearing fruits.
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.
After “how?", the second most-asked question we get about pruning is “when?” (Or, "Can I prune this now?") The rule of thumb is to prune immediately after bloom for flowering shrubs, in late winter or early spring for non-blooming shrubs (particularly for heavy pruning), and not after mid-August for any shrubs.
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.
You should only remove 10 to 20 percent of the tree branches from the edge of the canopy. Large trees benefit from removing end portions of limbs between 1 to 4 inches in diameter. Small ornamental landscape trees and fruit trees can be thinned by removing smaller limbs between ¼ to ½ inch thick.
Crown Raising (Fig. 4) Crown raising is the practice of removing branches from the bottom of the crown of a tree to provide clearance for pedestrians, vehicles, buildings, lines of site, or to develop a clear stem for timber production.
If you've got a fruit tree, summer pruning will promotes more blossoms (and more fruit!) the following spring. Fruit will mature better in sunlight, so allowing air and sun to reach the fruit will boost its size and sweetness.
Plants that bloom on old wood (last year's growth) are pruned after flowering so as not to remove flower buds with a winter pruning. Hedges also require additional shaping in early summer, and fruits need a little training.
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.
If you realize that your plant is root bound in the middle of Winter, it doesn't mean it's the right time to root prune it! All “invasive plant procedures” such as; repotting, pruning and root pruning need to be done in Spring, (Summer is OK too).
Choose the Right Time
Likewise, prune in the early morning or late afternoon to avoid the newly cut ends of branches becoming scorched by the hot sun. Wait 48 hours after rain to prune, to allow plants to dry out and avoid fungal diseases. When pruning, make cuts just above leaf nodes, or buds.
As a general rule, prune spring-blooming trees immediately after they flower. Prune trees that bloom in the summer or fall in late winter or early spring before the end of their dormancy. Routine pruning of dead or dying branches can be done at any time.
Differences Between Pruning and Trimming
Webb said pruning typically involves removing dead or diseased wood and thinning out stems and branches to improve the overall health and appearance of a plant. On the other hand, trimming typically involves cutting back plant material for reasons other than health concerns.
The cut is the key to good pruning. As a rule, always cut back to a branch, twig or bud that is pointed in the direction you want the tree to grow. This method encourages controlled, healthy new growth. If you're unsure whether to remove a branch, don't cut.
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.
The node is where leaves, buds and shoots emerge from the stem. You should always cut just above a node, as this prevents 'die back' and therefore disease. Also, by cutting above a node you can manipulate new stems, leaves or flowers to form in a desired direction, as nodes form on different sides of a stem.
For a tree to completely compartmentalize and seal off the exterior of a severed branch, it may take upwards of 15 to 20 years. However, within the tree, this containment process is fast-paced and extremely effective.
Follow these tips to prune your bush without killing it: Prune in the late winter or early spring before new growth begins. Cut back no more than one-third of the total length of each branch. Ensure all cuts are clean and sharp, angling them slightly away from the bush's centre.
Prune all evergreens, except pine, before new growth starts in the spring or during the semidormant period in mid-summer. When pruning, follow the general branching pattern to maintain the natural shape. Remove dead, diseased, or broken branches anytime.