Q • Our doublefile viburnums were just beautiful this spring and are now loaded with red berries, but several of the branches have upright shoots growing out of them, and I wonder if we should be doing anything about them?
A • Vigorous, upright, vertical shoots (watersprouts) are not uncommon on the doublefile viburnum (Viburnum plicatum var. tomentosum) and are best removed as soon as they are noticed when they can be easily rubbed or pinched off with your fingers. Larger watersprouts can be removed in late winter, while the shrub is still dormant. If allowed to remain, they will eventually become thick, secondary trunks and detract from the normal layered, horizontally branched natural habit of this spring-flowering shrub.
Other than watersprouts, prune as little as possible once the natural framework of the shrub has become established, removing crossing branches that rub and interfere with one another. Dead wood can be removed at any time. In my experience, the older a doublefile viburnum is, the less tolerant it is of heavy pruning. Plants that are pruned heavily are more likely to sprout a profusion of watersprouts and are subject to dieback. The handsome red berries are almost as ornamental as flowers for a short period of time, and will ultimately turn black when fully ripe, provided the birds don’t devour them beforehand.