Pruning can be done almost any time of the year, but there are optimal times for plant response. In fact, timing is everything for some plants. A plant's energy reserves are highest during the dormant period of winter and lowest during spring growth. If plants are pruned during the action weeks of spring, they may draw on diminished reserves to replace at least part of the lost growth and to defend pruning wounds. Late summer and early fall are also poor times to prune, because this may encour age new growth that will not mature sufficiently to withstand winter freezes and may be killed by an early fall frost. Finally, avoid pruning in late fall or early winter. The wounds could stay open until spring, inviting dessication. An old rule is do not prune when the temperature is below 20 F.
The best time to prune is late winter or early spring, before buds start to swell and open. At this time, the possibility of freeze damage is reduced. Plants have plenty of stored energy and are ready to grow. Dormant pruning may reduce the amount of flowering on shrubs that flower in spring, but occasionally it is necessary to maintain the desired growth form. Prune birch, elm, maple and yellowwood in late winter. These trees are known as 'bleeders,' and when pruned in spring, the flow of sap is unsightly and can stain the tree bark.
The next best time to prune is in early summer after all the foliage has matured. Wait for a day when the foliage is dry, especially if diseases such as mildew or fire blight are evident. Use this pruning time to control height or to develop a denser shrub.
Trees and shrubs should be examined for pruning on an annual basis. Too many homeowners neglect their shrubs and fail to prune for several years. Shrubs become overgrown (a loss of vigor may occur) requiring heavy pruning or severe renewal pruning to reduce the size of the plant. Never hesitate to cut out tall, fast-growing or unsightly limbs while they are growing. If the terminal bud is pinched or lightly pruned on new growth, lateral growth will occur and result in a fuller plant.
Was this article helpful?