It is winter and the leaves are gone, making it easy to see the structure inside deciduous woody ornamental shrubs. Three reasons shrubs are pruned are to:
+ keep them shapely
+ encourage better quality blooms by reducing the amount of wood so energy is diverted into the production of fewer but larger flowers
+ maintain plant health by eliminating dead, dying, or diseased wood, possible entry points for insects or diseases
I’m not talking about “shearing” as is done with a dense, solid, usually evergreen hedge. Nor is pruning the best way to keep a shrub “short”. For that, [hopefully] the initial plant selection considered the location and the ultimate height of the shrub. Only last night I remarked at our car repair shop that they were going to be involved in a lot of pruning based on the five red-leaved Loropetalum newly planted beneath a low picture window. Each plant alone has the potential to obliterate the entire window, reaching over 10 feet in height! It looks like constant pruning is going to be necessary, when the choice of a dwarf-growing variety would have eliminated this maintenance issue.
A shrub is defined as a woody plant having multiple trunks or woody stems arising from the base at soil level. Sometimes these get too crowded, with criss-crossing stems inside the shrub. Pruning allows air to circulate within the crown and the leaves to dry off more quickly after dew or a rain.
Then there is the spring-blooming and summer-blooming controversy. Now, it’s true, pruning a spring-blooming shrub in late winter means that some of the flower buds which formed last fall will be removed, reducing the overall number of flowers to be enjoyed. However, I think the benefits of being able to see the plant’s multi-stemmed structure while the leaves are off compensates for this reduction of flowers, and will certainly be justified next spring.
Armed with sturdy gloves and sharpened by-pass pruners:
+ First, trim away any branches that are rubbing against others
+Next, prune branches that are growing toward the center of the shrub, allowing outside branches to flourish
+Finally, remove stout branches of old wood at the soil line, leaving vigorous young branches that will grow, flower and restore a youthful habit to old, overgrown shrubs
I like to prune toward the end of winter, so I'm putting it on my gardening calendar for late February. This way I can observe any winter kill and prune accordingly.
Drawings courtesy qwickstep.com, Virginia Tech Extension, photo Garden Debut(R) Admiration Barberry PP16921