In spring, every garden center and parking lot pansy stand tempt winter-weary gardeners with irresistible blooming shrubs in little 1-or 2-gallon pots. But before you plant that forsythia or lilac under your picture window, imagine this label stuck on the pot -- WARNING: This cute little shrub may soon grow significantly larger than it now appears!
Large-growing shrubs planted in the wrong place block windows, crowd sidewalks and doorways and quickly outgrow allotted space. Fortunately, there are dozens of excellent shrubs available that top out at 4 feet tall or less, making them ideal for many landscape situations. Foundation plantings are one good use for small shrubs, but don't limit these little lovelies to that all-too-common fringe along the front of the house.
A few small shrubs, especially some of the dwarf conifers, are special enough to be featured singly, but most small shrubs look best planted in multiples. Planted in groups, small shrubs serve as a tall groundcover or create a smooth transition between low-growing turf areas and taller shrubs and trees. Small shrubs that tend to spread by suckering and rooting along the stems are ideal for planting on slopes or steep banks: Good choices include 'Gro-Low' fragrant sumac, dwarf cutleaf stephanandra and the shade-tolerant natives bush honeysuckle and red coralberry.
Small shrubs also make great hedges, either formal (like sheared boxwood) or informal (dwarf Meyer lilac, for example). They're too short to provide privacy screening, but low hedges are wonderful for guiding the eye through the landscape, defining areas within a landscape, or softening hard lines such as patio or driveway edges.
One creative way to use small shrubs is in combination with perennials. Such mixed beds or borders are a standard feature in many famous English gardens. But there are plenty of ways to mix it up in your own slightly less famous garden. The ornamental features available in small shrubs -- flowers, colored or variegated foliage, colorful fruit and fall foliage -- can complement the blossoms and foliage of blooming perennials and ornamental grasses.
Pair the subtle leaf-margin variegation of 'Carol Mackie' daphne with the elegant pinstripes of variegated feather reed grass (Calamagrostis x acutiflora 'Overdam'), then mix in red-flowered cultivars of peony, daylily and hardy chrysanthemum for a long season of bright accents. Add a 'Red Sprite' winterberry to carry the red theme into the winter. Such combinations of small shrubs and perennials provide many opportunities for multi-season interest in the garden.
Size does matter
Selecting the right size shrubs for your yard and garden requires some research. With several groups of shrubs (such as potentillas and summer-blooming spireas) you can select any cultivar in the group and be confident that it will fit in the "under 4 feet" group. But other shrubs can have a wide range of sizes within the many named cultivars. For example, most mock-orange cultivars reach a lanky 6 feet or more, but the compact cultivar 'Miniature Snowflake' grows only about 3 feet tall.
The size range in conifers is even more dramatic. Norway spruce (Picea abies) can tower up to 80 feet, but the species has spawned many dwarf cultivars, such as the 3-foot-tall bird's nest spruce (Picea abies 'Nidiformis') and the even smaller 1-foot tall 'Little Gem.'
When you shop for small shrubs, check labels and, if you're unfamiliar with a cultivar, ask a knowledgeable nursery worker about the shrub's mature size.
Pretty potentillas
Don't judge potentillas just by the straggly specimens seen at gas stations and fast-food drive-throughs. Potentillas are tough plants, surviving the poor soil conditions and drought at those less-than-ideal growing sites, but they can look much better in the home landscape. Rejuvenate these prolific yellow-, white-, orange-or pink-flowered bloomers in early spring by either cutting back all stems to the ground or selectively thinning out about one third of the stems each year -- you'll be pleasantly surprised by how much this improves their appearance.
Surprising spireas
'Summer-blooming spireas' describes several types of spirea, but the main group is Japanese spirea and its many cultivars (Spiraea japonica and the related hybrid S. x bumalda). These spireas bear pink flower clusters in early to mid-summer and several cultivars have colorful red-bronze new growth and/or golden foliage.
Birchleaf spirea, Korean spirea and Japanese white spirea also are summer bloomers, but they sport white flowers. Many summer-blooming spireas also develop yellow, bronze, orange or red fall color. If you prefer the frothy white flowers of spring-blooming spireas but don't have room for the full-size varieties, try the romantically named 'Fairy Queen' or 'Swan Lake'; both top out at 3 to 4 feet.
Color in a small package
If you're looking for small shrubs with richly colored summer foliage, the red-, purple-and golden-leaved cultivars of Japanese barberry are for you. Plant the striking burgundy-and-pink variegated 'Rose Glow' with a pink-flowered hardy shrub rose like 'The Fairy' and then sprinkle in blue-flowered perennials such as delphiniums, blue hyssop or Russian sage for a charming combination. Golden-leaved cultivars such as 'Aurea' and the dwarf 'Gold Nugget' provide dramatic landscape highlights -- just don't overdo it.
Shrubs for hardscapes
Whether installing a simple foundation planting or designing an elaborate rock garden, you'll find plenty of just-right sized shrubs to do the job. This spring, instead of continuing to fight with that overgrown Pfitzer juniper or misplaced dogwood, consider digging out the old and starting fresh with small shrubs that will stay in their assigned seats.
Select a combination of deciduous and evergreen small shrubs with a range of ornamental features. Add some perennials, grasses, ground covers or larger shrubs as appropriate, and you'll be well on your way to a beautiful, low-maintenance addition to your landscape. The dead of winter (when you can dream big but don't have to actually wield a shovel) is a great time for planning, so grab some garden catalogs, books and magazines and start thinking "Small is beautiful."
-- Nancy Rose is a Twin Cities horticulturist, writer and photographer. She finally ripped out her overgrown foundation planting last year and is planning wonderful things for the spring.