Pruning Calendar — Seattle’s Favorite Garden Store Since 1924 – Swansons Nursery

One of the more common questions asked by newer gardeners is, “when is the best time of year to prune my __________?” The answers out there can vary from “the first hearing of tree frogs after the second full moon past the Summer Solstice” to “anytime your pruning shears are sharp.”

Here in the Maritime Northwest, we recommend that most pruning be done during summer and winter, and minimize it during fall and spring, which are more sensitive periods when the sap is flowing. In warmer or colder climates (particularly where more extreme), timing recommendations may differ, depending on how local plants grow, when they bloom, etc. It’s best to check with local resources before establishing your pruning schedule.

Keep in mind that these are general recommendations. Appropriate timing for pruning is helpful, but perhaps not critical to a plant’s health and performance. Young trees and shrubs, fruit-bearing plants, and delicate flowering plants may be more sensitive but generally, a healthy plant can tolerate pruning almost any time, outside of periods of extreme heat or cold. Dead branches and twigs can me removed any time, of course. And most plants don’t require pruning every year if they are grown in an appropriate space.

More important is how much you prune off at one time and where you make your cuts (visit our post Pruning 101 for details). With experience — and by keeping your pruning moderate and gradual — you will avoid major mistakes or overreactions, learn what your plants can tolerate, and establish your own rhythm.

SPRING

Spring is a dynamic, and therefore, delicate season for pruning. It’s when plants are leafing out, sap is most active and pruning can disrupt fragile new growth, flowering, nesting birds, or pollinators. It might help to think of early, mid, and late spring as three phases for pruning before, during, and after the primary growing period. Then avoid or minimize any pruning in mid-spring.

A general principle is that pruning before the primary growth season tends to accelerate growth, whereas pruning after that season tends to slow it down. There are exceptions, depending on species of plant and how healthy or vigorous an individual plant might be.

Early spring (typically between late February and early April in our region) is okay for cutting back perennials, ornamental grasses, vigorous shrubs (unless they are spring-blooming), and hybrid roses. Any major, aggressive pruning you deem necessary is better done in early summer, or winter as described later.

Mid spring (April and May) is okay for light thinning or corrective pruning of a tree or a young plant, along with cutting some branches for flower displays. But again, keep this pruning minimal.

Late spring (June) is when you can prune plants that have finished blooming and cut back more vigorous growth, although some growth might not slow down until early July around here.

So if your garden tends to go crazy each spring, wait for summer to do most pruning. But for some aged or struggling plants that seem to lack vigor, a hard pruning in early spring may give them a jump start. Also, if your English laurel or other fast-growing, coarse-branched hedge needs a major cutting back, doing so in early spring can help it regrow quickly and minimize the “chopped” look, although it might still need some additional pruning in summer.