I read a few years ago about a research project about pruning hardy shrubbery to the ground each fall, treating them as if they were perennnials. I do this with some spiraeas on the university campus in alaska, but wonder about any other experiences others have Davelll
Any kind vigorous enough to tolerate it and flowering on new wood is suitable. Less vigorous kinds will become weakened by repeated loss of nutrients stored in stems. Those flowering on old wood only will not flower because they have no old wood. <i>Spiraea japonica</i> is generally easy and flowers on new wood but when I cut down a 'Goldflame' here it didn't bounce back all that strongly. It is, however, a shaded specimen under an oak tree.
I do this every year with two Cotinus coggygria that I take care of.they do very well. they never bloom,but I like the new folage better than the blooms anyway.And it keeps them at a shorter heighth.
Others have praised cutting down Cotinus but I find they come back all snakey, like they were trying to find their lost heads.
Cutting overgrown shrubbery to the ground every now and then can be rewarding--it can produce better results than merely whacking bushes back. Quite a number of more-or-less tropical woody plants behave as perennials at the northern limits of their ranges. In eastern North America, Erythrina herbacea is a great example. In southern Florida, it's somewhere between a big bush and small tree, while in northern Florida it's definitely an herb. Some fire-adapted shrubs very nearly function as herbs. In Florida, Asimina and the closely-related Deeringothamnus (pawpaws) flower profusely when resprouting from a fire that's destroyed the above-ground parts. This sort of behavior extends to Nolina (beargrass, an agave relative), Serenoa (saw palmetto), and even some oaks. Many forest shrubs are quite good at surviving falling debris. Of course debris tend to rot faster in eastern North America than in the Pacific rainforest zone! (Off topic, there's pathological mutilation of shrubbery--an outfit called Plant Amnesty in Seattle deals with this).
