Venture out to the garden while sheltering in
A lot of us are at home, following Gov. Pritzker's order to shelter in. But sheltering in doesn't mean we can't go outside to the garden. In fact, some fresh air may be just what we need. As long as the soil is dry enough to walk on, why not use the time to start cleaning up perennial borders?
Grab your pruners and head out to the garden. However, before you start cutting, there are some decisions to be made. Some perennials get cut back all the way to the ground. Others are just tip pruned, and the dead or ugly leaves are all that is removed from some perennials.
So how do you know what kind of pruning to do? Some perennials have low rosettes of basal foliage that remain during the winter. These ground-hugging leaves protect the roots when the rest of the plant dies back in winter.
Begin pruning these perennials by cutting back the dead stems first and then assessing the condition of the basal foliage. If you are a neat-freak type of gardener, winter-ravaged basal foliage can be trimmed, too, but it is tedious and unnecessary. New spring growth will quickly grow to cover old foliage and freshen the appearance.
Examples of these perennials with basal foliage include bellflowers (Campanula), coreopsis, Shasta daisies (Leucanthemum x superbum) and yarrow (Achillea millefolium).
Sedums have succulent basal foliage. Removing dead stems allows sunlight to encourage new growth.
Some evergreen perennials, like pinks (Dianthus) and moss phlox (Phlox subulata), need little if any pruning. If winter was especially hard on them, wait until they have bloomed and then cut them back by half.
There are a number of perennials that are cut back depending on the kind of winter we have had. In years with reliable snow cover, a blanket of snow protects the foliage of semi-evergreen perennials and they need little pruning. Years with especially cold temperatures or periods without snow cover damage their foliage and most of their foliage needs to be cut back.
Examples of these include Bergenia, Epimedium, coral bells (Heuchera), foamy bells (Heucherella), foam flowers (Tiarella) and some ferns.
Woody perennials, like butterfly bushes (Buddleia), lavender and Russian sage (Perovskia), are best left standing until new growth begins. These are then tip pruned down to plump healthy buds. Unlike the name suggests, tip pruning does not necessarily mean just the tips of stems are cut. Instead, it means stems are cut back to robust new spring growth. The type of winter will determine how far down from the tips of the stems that will be.
Most winters cause some of the foliage of sedges to brown. If you have a lot of time on your hands, dead leaves can be removed individually. Or put on a pair of rubber gloves and use your fingers to comb through the foliage to get the majority of damaged leaves to fall.
Most of the rest of perennials fall into the cut all the way to the ground category. And much of this foliage will simply pull from the ground without the use of pruners.
• Diana Stoll is a horticulturist, garden writer and speaker. She blogs at gardenwithdiana.com.