Pruning is the art and science of removing or shortening branches of a tree or shrub. If done correctly, it can prevent breakage, increase beauty and increase flowering and fruiting. To learn how to make a healthy cut, study the Shigo method of pruning, or come to one of Mikl’s pruning classes.
What follows is some general guidance:
- Prune shrubs that flower in late summer and fall
(after they have bloomed): Rose of Sharon, Fernbush, Apache Plume, Hydrangea, Buddleia, Spirea, Rabbitbrush, Russian Sage, Blue Mist Spirea, Potentilla
- Also you can prune fruit trees and roses that repeat bloom (not if they only bloom in the Spring).
- And anything that is desperately in need, like tall and floppy or droopy growth, or branches heavy with seeds
In general, the best time to prune is right after flowering ends.
- Grasses are best left for winter beauty, and pruned down to 2”-3” in early spring.
- If not before, in fall, prune the thin branched shrubs like Potentilla, Broom, Spirea and Mockorange. They benefit from shearing to compact the form and prevent the branches from being smashed into the mud by wet snows. This is best done every year after flowering. I usually prune 3”-5” with hedge shears to remove the old flowers and seeds. You can follow a natural form but it’s best to shape to a roundish form with the highest part over the center so that the snow falls off.
- Old shrubs with big wood can be rejuvenated by removing 3 to 5 of the biggest, oldest stems back to the ground, and shortening the long and lanky growth by 10%-20%.
- You can prune spring-blooming shrubs in the fall if they are likely to break in winter snows or that are just too tall, but you will lose some or most of next year’s flowers and fruits.
- If a shrub has berries or fruit, you can leave them for the birds, and prune right after the fruit is picked or falls.
- If a shrub is very broken, ugly, or old and you are considering removing it, cut it to the ground in the fall, and it may come up rejuvenated in spring.