Lilacs’ romantic looks and honeyed fragrance evoke Victorian gardens and sumptuous bouquets. In full spring glory, the soft, panicled blooms of lavender, purple, white, or pink bedeck the bushy shrubs, inspiring ooohs and ahhs. If only the show lasted longer: After just two weeks, the flowers fade, transforming most lilacs into plain shrubs with little landscape appeal. For this reason, they’ve become unpopular with design-savvy gardeners and are grown only by diehard fans (or those who inherit them with their old houses). But this doesn’t have to be the case. A few lilacs break the mold by offering long-lasting good looks without shirking on flower quality.
The long history of lilacs is comparable only to that of roses, lilies, and tulips. The most familiar common lilac (Syringa vulgaris) is a large, multi-stemmed shrub from the mountains of southeastern Europe. Its voluptuous, fragrant blossoms were first brought to the courts of Vienna in the 1500s, and their popularity rapidly spread throughout northern Europe. In the 1600s, they were imported to the New World by colonists seeking a piece of home. By the Revolutionary War, lilacs were common across eastern North America and eventually moved westward with pioneers.
The flowers were ubiquitous in 19th-century paintings, songs, and poems. Claude Monet’s Resting Under the Lilacs (1873) depicts a time when they were an Old World garden standard—a popularity echoed in New World works. “The Lilac” (1888), a classic American song by Gustave H. Kline, tells of love shared through lilac blossoms, and Walt Whitman’s stirring poem “When Lilacs Last in the Dooryard Bloom’d” (1900) speaks of lilacs as an eternal symbol of spring. Americans commonly planted lilacs near their entry doors, where the delicate spring flowers could be most appreciated.
It’s hard to say when lilacs fell out of favor, but most point to a gradual shift in gardeners’ needs. Landscape design and “curb appeal” took precedence over the fleeting beauty of seasonal flowers, and lilac breeders didn’t help the cause by continuing to focus on bigger, better blooms rather than long-term good looks and higher pest and disease resistance. In his latest Encyclopedia of Trees and Shrubs, author Michael Dirr writes of common lilacs, “It is unfortunate that such a treasured shrub with such wonderfully fragrant flowers should [still] have so many flaws.”
That said, there are some lilacs that break the mold. Several new varieties and revered species alter the status quo by providing continuous beauty to the garden.
The compact Bloomerang Purple® is the poster child for new lilac breeding with its pleasingly low, bushy habit (3′ x 5′), and ever-blooming branches that produce large, fragrant purple flower clusters all season, as long as summer’s heat doesn’t get too high (above 85 degrees during the day and 75 at night—it’s the warm nighttime temperatures that usually inhibit growth). Bloomerang even resists powdery mildew, the number-one foliage disease of lilacs. Plant it along a sunny foundation or in a large container.
One of the most popular landscape lilacs is the Manchurian ‘Miss Kim’ (Syringa pubescens ssp. patula ‘Miss Kim’), and it’s easy to see why. The round, dense shrub reaches 7′ and has pretty, pale lavender-pink flower clusters that are mid-purple in bud. Its disease-resistant oval leaves are medium green, turning attractive shades of burgundy-red in fall—unlike most other lilacs, which lack fall color. It’s an ideal shrub for large foundation plantings.
If you’re looking for a rounded, statuesque lilac with old-fashioned looks and strong disease resistance, then try Syringa ‘Old Glory.’ Bred at the U.S. National Arboretum, it bears many fragrant, bluish-purple flowers in early spring. Though slow-growing, it will eventually reach a height of 11′, so it’s best planted as a showpiece on an open lawn.
Tough, adaptable, and beautiful, littleleaf lilac (Syringa pubescens ssp. microphylla) is a rounded, spreading Chinese native with consistent good looks. In late spring, it bears highly fragrant lavender-rose flowers that shine above small, clean gray-green leaves. These may bloom again in late summer or fall, if growing conditions are not too stressful—too hot or too dry—and plants are planted in a good location with fertile soil and enough sun. Seek out the old-fashioned variety ‘Superba,’ which has rich pink flowers, and plant it in a large, open shrub border where it can reach peak potential.
As its name suggests, the early lilac (Syringa oblata var. dilatata) begins its blooming season sooner than other varieties. Starting as early as March, the early lilac bears loose panicles of slender, lilac-purple flowers with light fragrance. The uniformly rounded variety ‘Cheyenne’ (6′ to 8′) grows well in the Deep South and bears loads of delicate lilac-blue flowers that are pink in bud. It also boasts glowing burgundy-bronze fall color. Plant as a specimen or add to a spacious, opulent shrub border.
Lilacs need a few basics for good health. A site with full sun and ample airflow will encourage the best habit and flowering while discouraging foliar diseases like powdery mildew. It’s also essential to plant lilacs in average to fertile soil that’s slightly alkaline to neutral and has good drainage. Bone meal is a good, all-natural fertilizer for lilacs and should be spread around the canopy shadow at the rate of ¼ cup for every ¼” of trunk diameter. These remarkably hardy shrubs grow best in cold climates, often tolerating USDA hardiness zones 3 and 4, but may become stressed in areas with hot summer days and nights (daytime temperatures over 85 degrees Fahrenheit and nighttime temperatures over 75), so Southern growers should choose heat-resistant lilacs like ‘Cheyenne.’
Pruning should be done sparingly, if at all. Most lilacs bloom on old wood, so prune just after flowering. Dead or lilac-borer-infested stems can be removed at any time. Borer damage is easily identified by round or half-moon-shaped exit holes that appear at stem bases. Old, ungainly lilacs can be rejuvenated by cutting back the oldest stems by one third while retaining the strongest new shoots.Published in: Old-House Journal April/May 2013