Knowing a good pruning technique can mean the difference between success or failure when you are raising vegetables, trees, shrubs or any other type of plant. Pruning away overgrown foliage can expose to sunlight parts of the plant that are blocked from it, ensuring even and healthy growth. Many plant diseases are controlled by pruning back infected parts of the plants. Pruning is also one of the best ways to keep a good aesthetic to your garden by trimming back trees that have grown out of their desired size and shape. For magnolias, properly timing your trimming is a key to success.
Magnolias and Pruning
In general, magnolias need very little pruning when they are full-grown. When planting your infant magnolia tree, make sure to understand the maximum height and width of the magnolia cultivar you purchased and to plant it far enough away from neighbouring trees that the magnolia can reach this maximum size without crowding. If the magnolia outgrows this maximum size, it is crucial to prune it to preserve its health.
When to Prune
If you are planting new magnolia trees, prune off any dead, diseased or broken branches and discard. As noted, magnolias do not require regular pruning but only need to be pruned when they grow larger than the desired growing area. (According to Texas A&M University, recent research has dispelled the myth that trees should have their top one-third of growth trimmed away when transplanting to soil to compensate for root loss.) Less significant cosmetic issues may also require some occasional pruning, such as two branches rubbing against one another and causing open wounds on the tree or if certain parts of the tree become infected by disease or are damaged by pests.
How to Prune
To prune a magnolia that has grown out of its desired shape, locate the tallest or widest branches and cut them back rather than cutting a multitude of branches into a lollipop shape. This approach preserves the tree's natural growth pattern and does not harm the flesh of the tree as much as pruning multiple branches. Magnolias should be pruned in midsummer so that they have enough time to heal before the next spring flowering season. Use a pair of hand-held pruning shears for small branches and a larger pruning lopper or small saw for larger branches.
Pruning is, in a technical sense, deliberately damaging a tree to produce desirable results. Another key to successful pruning, then, is to use a pruning technique that damages the tree as little as is possible. Always sharpen your pruning equipment before use; this will result in a smooth, quick cut. Avoid tearing or twisting off any branches that do not come away with sawing alone. Prune at an upward angle, not too close to the boot, but also not leaving a "stub" that could spread disease.