Draped with a cloud of heady blooms, these long-lived shrubs reliably perfume the spring landscape year after year.
Celebrate spring’s arrival with lilacs. Like clockwork each May, these venerable shrubs wake up landscapes groggy from a long winter’s nap with a profusion of flowers and fragrance. For nearly two weeks, wands of purple, pink, or white blooms waft spring’s sweet perfume through the garden.
North American gardeners have a deep-rooted love affair with these durable shrubs. It might have something to do with the flowers’ distinct fragrance, which is unmistakable even to nongardeners. Or maybe it’s just because we know the predictable spring bloom signals the beginning of the planting season.
Lilacs hold a place in our hearts for many reasons; likewise, they claim a respected place in the garden. Easy-to-grow shrubs, lilacs thrive in full sun and well-drained soil. After blooming in May, the shrubs’
medium green foliage becomes a lush backdrop for summer- and fall-blooming plants. Care is simple: Lilacs require only an annual pruning after blooms fade to maintain the shrubs’ shape.
Select Your Shrub
When carefully selected and planted, lilacs regularly outlive the person who plants them. Their tenacity explains why lilac hedges bloom with abandon on forlorn farmsteads across the Northeast and Midwest. The genus Syringa is made up of more than 20 species. The runaway favorite is the common lilac (Syringa vulgaris), known for its heady fragrance, bushy habit, and mid-May bloom time.
Most lilacs thrive in Zones 4–7, but researchers also have developed a number of species and
cultivars that grow in Zones 2 and 3, as well as
Zone 8. Preston lilac (Syringa ¥ prestoniae) and hyacinth lilac (Syringa hyacinthiflora) are prized for their ability to display showy blooms in chilly
Zone 2. Chinese lilac (Syringa ¥ chinensis), some cultivars of common lilac, and dwarf Korean lilac
(S. pubescens subsp. patula) bloom year after year in Zone 8 and the northern fringes of Zone 9.
It’s important to note mature size when selecting your lilac. Common lilacs mature at about 12 feet tall and 8 feet wide, while dwarf species and cultivars may grow to half that size. Japanese tree lilacs (Syringa reticulata) can reach 25 feet tall. Situate lilacs where they have ample elbowroom. Unsightly powdery mildew becomes a problem in crowded plantings, reducing the bloom power of the plant.
Into the Landscape
The lilac’s lofty stature makes planting it in today’s smaller landscapes a challenge. But take heart; a plethora of dwarf cultivars are on the market, developed specifically for petite planting places. With annual pruning, you can maintain these lilacs at a manageable size. Plant them where you can enjoy their fragrant flowers. A sunny site near a patio or deck will perfume your outdoor dining room. Or plant a lilac 8–10 feet from a window, where the sweet scent can waft indoors.
Lilacs form dense screens when grouped. They also can be included in mixed shrub borders and large perennial borders. Create a nonstop vignette of color from early spring to late fall by pairing lilacs with companions known for fabulous foliage and spectacular bloom. Tulips, irises, creeping phlox (Phlox subulata), and peonies add color in spring. Purple coneflower (Echinacea purpurea), garden phlox (Phlox paniculata), and garden sage (Salvia spp.) bloom reliably in summer, and asters, Viburnum, and ornamental grasses carry a mixed planting into fall.
Prune with Gusto
Annual pruning is the most important thing you can do to ensure a healthy lilac and a profusion of blooms the following year. Common lilacs tend to send up suckers that can turn a tidy shrub into a forest of wayward stems. Begin pruning by removing dead or diseased branches. Then cut some of the oldest and largest stems at ground level. Thin out young suckers so that only 10–15 shoots of various ages remain. Cut the remaining new, vigorous shoots back by one-third to a healthy branch union.
Get a jump start on pruning by snipping clusters of flowers just before they fully open, then enjoy the fragrance of spring indoors. Whether enjoyed indoors or out, the perfume of lilacs serves as a sweet reminder that spring has sprung once again. Let the gardening season begin!