Some of my favorite shrubs are oversize, meaning that when they mature they’re really too large to fit in most landscapes. I like to call them “big old-fashioned lawn shrubs”. Examples include many varieties of lilac, hydrangea, ninebark, forsythia and viburnum. These are huge plant families, of mostly huge plants.
When we’re designing landscapes we choose plants by their full-grown width (spread) and height, so that they won’t outgrow the space, block walkways or windows, or overpower the other plants in the landscape. It helps to actually see mature examples of these plants, before deciding whether they are right for your particular yard. Many landscapers and home gardeners simply plan on cutting and shearing plants to contain their size, but this can be risky.
More often than not, attempts to contain large shrubs by cutting them down to size will ruin their natural beauty. We call this “playing God”; deciding that we know better than their Creator what size and shape plants should be. This is a lot of work. Most shrubs benefit from annual shearing each year until they mature, but this shouldn’t be an attempt to make them smaller. Proper shearing leads to stronger branch structure, more bloom, and a pleasing mounded shape. Shearing to control size is a losing battle.
Plant breeders are constantly working to miniaturize our favorite large shrubs, trying to widen their appeal. Homeowners seem to prefer shrubs with a maximum size of three to four feet, so breeders hope to sell more lilacs, butterfly bushes and hydrangeas by inventing smaller, more compact varieties. The word “dwarf” is probably the most-often heard request at nurseries, so breeders often stretch the truth by just assuming that you’ll routinely cut your shrubs down to size when they outgrow their space.
Large shrubs have their place, perhaps even in your landscape. They provide eye-level privacy screen, filter out dust and noise, mask unsightly views, and put on a real show when they bloom. Think “old-Fashioned Snowball Bush” (Viburnum opulus), old-fashioned lilac (Syringa vulgaris), and the many varieties of sun-loving hydrangea. There’s no better privacy hedge than leatherleaf Viburnum (ten feet tall and wide in sun or shade). A huge “Limelight” hydrangea is the undisputed king of our garden, reigning supreme at ten feet tall and twelve feet across, covered with bloom from early July through the winter months. We’ve sheared it for shape every year, but I wouldn’t think of trying to contain it at three to four feet.
Landscaping with “large at maturity” shrubs takes some guts and some planning. You must allow for the final size of the plant when spacing your garden, and tolerate a large empty space around it for as long as it takes to grow full-size. An easy solution is to plant large shrubs in open lawn, gradually enlarging the mulch circle around it each year.
Stand at your kitchen sink, or relax on your porch or deck. Is there something unsightly in your field of view? Try planting some sort of large-at-maturity shrub in the line of sight between you and the eyesore, and then just let it GROW. Nothing to be afraid of.
Steve Boehme is a landscape designer/installer specializing in outdoor living spaces. “Let’s Grow” is published weekly; column archives are online at www.goodseedfarm.com. For more information call GoodSeed Farm Landscapes at (937) 587-7021.