pruning—usually within a week there will be new growth, and in 2 weeks you’ll
have a full, lush plant again. A word of caution is in order when it comes to using
hedge shears or string trimmers: be sure that the individual wielding the tool is
trained in the way the pruning should be performed, both from the plant’s point
of view as well as from the operator’s, otherwise unintended cuts may be
encountered. Unless you have a lot of time to spare—and most people don’t these
days—if using hand pruners, simply grab a handful of stems and snip, rather
than doing an individual stem at a time.
I will discuss cutting back for maintenance and aesthetics, for height control,
as a means of delaying or preventing flowering, and as a regenerative technique.
Given the complexity of this topic, I have placed plants into categories based on
their flowering time: spring, summer, or autumn. As with most living things,
plants don’t always fit into neat categories, but it does help in simplifying this
otherwise confusing information. The Encyclopedia of Perennials provides
detailed information on the best techniques for specific plants.CUTTING BACK FOR MAINTENANCE OR
AESTHETICS—PRUNE AFTER FLOWERING
Perennials that are being cut back for purposes of maintenance or aesthetics
should be pruned after flowering. Generally when plants are cut back after
flowering, the regrowth remains lower than the normal mature height of the
plant, and if rebloom occurs, the flowers often will be smaller in number and
sometimes in size. In many cases, when pruning after flowering it is best to cut
down to the start of new growth developing at the base of the plant, or the basal
foliage. Personally, I am more comfortable pruning a perennial down to basalRegrowth on Symphyotrichum
novae-angliae ‘Andenken an
Alma Pötschke’ 2 weeks after
pruning.
108 PruninG Perennials