Can I Prune This Shrub Now?
As we move into fall I do a fair bit of pruning. Trees and shrubs don’t mind getting a haircut, but you need to know this: if you prune a spring-blooming tree or shrub, you are cutting off blossom buds when you prune.
Diablo after a recent haircut.
I just tuned up my ‘Diablo’ common ninebark. It is a fast-growing shrub with dark purple leaves and it gets gawky if I don’t prune it at least once a year. But pruning it now, I won’t get much of a show next spring. That’s okay, I’d rather see a tidy shrub all winter than leave awkward stems reaching skyward or sideways. And the blossoms are not dramatic anyway. I grow it for the foliage.
I prune this lilac every summer to keep it small.
Lilacs bloom in May. Each summer they establish buds that will bloom in the spring, so I generally prune right after they blossom. Any shrub that blooms before the Fourth of July sets its blossoms the year before.
February Daphne blooms in May here. I named my corgi after this lovely, fragrant shrub!
Here are some of the spring bloomers that have already made their buds: Shad bush (Amelanchier spp.), Eastern redbud (Cercis Canadensis), daphnes of all sorts, forsythia, apples and crab apples, lilacs, magnolias, rhododendrons, viburnums and wisteria. You can prune these now, or in early spring, but you do lose some flowers.
If you want to do some pruning now, go for it. You won’t harm the shrub or tree. And it will look better all winter.