If there is one shrub Northerners wish they could bring with them to the South, this is it. No plant is more cherished than lilac for big, flamboyant, fragrant flowers. Most popular are the common lilac (S. vulgaris) and its scads of selections, but many other species and hybrids merit attention. Most are medium-size to large shrubs with no particular appeal when out of bloom. Leaves are typically oval and pointed or rounded, with smooth edges. Floral show (always after leaf-out) comes from numerous small flowers packed into dense clusters shaped like pyramids or cones. Depending on where you live, flowering may occur anywhere from earliest spring to early summerthat is, if flowering occurs. Like the Green Bay Packers, most lilacs are used to long, cold winters, and without that chill they are likely to perform poorly. This disappoints folks who are looking for the same spectacle in Atlanta that they enjoyed in Bangor. Some types, however, such as S. x laciniata and others described here, bloom well with only light winter chill and put on a good show even in the Lower South. Most lilacs won't bloom in the Coastal Southand certainly not in the Tropical South.
S. x chinensis. CHINESE LILAC. Zones US, MS; USDA 6-7. Hybrid between S. vulgaris and S. x persica. To 15 ft. high and wide, usually much less. More graceful than S. vulgaris, with finer-textured leaves to 3 in. long. Profuse, open clusters of fragrant, rosy purple flowers. Does well in mild-winter, hot-summer climates. 'Alba' has white blossoms. 'Lilac Sunday' is a vigorous, disease-resistant selection with light purple blossoms.
S. x hyacinthiflora. Zone US; USDA 6. Group of fragrant hybrids between S. vulgaris and S. oblata, a Chinese species. Resemble S. vulgaris but generally bloom 7 to 10 days earlier; unreliable bloom in most of the South. 'Asessippi' (lavender) and 'Mount Baker' (white) are earliest. Other selections include 'Alice Eastwood' (double magenta), 'Blue Hyacinth' (lavender), 'Clarke's Giant' (lavender; larger flowers than others), 'Esther Staley' (magenta), 'Excel' (light lavender), 'Gertrude Leslie' (double white), 'Maiden's Blush' (pink; excellent performer), 'Pocahontas' (purple), and 'Purple Heart' (purple).
A group of complex hybrids developed by the U.S. National Arboretum include uniform, heavy-blooming, disease-tolerant plants, some of which thrive in the Middle South (USDA 7). Look for 'Betsy Ross', to 10 ft. tall, 13 ft. wide, with large white flowers; 'Declaration', to 8 ft. tall and wide, with reddish purple flowers; and 'Old Glory', to 12 ft. tall and wide, with bluish-purple flowers.
S. x laciniata. CUTLEAF LILAC. Zones US, MS, LS, CS; USDA 6-9. Open-structured plant to 8 ft. tall, 10 ft. wide. Leaves to 212 in. long, divided nearly to midrib into three to nine segments; good rich green color. Many small clusters of fragrant, lilac-colored blooms. Highly mildew resistant. Blooms well even in Lower and Coastal South.
S. meyeri. MEYER LILAC. Zones US, MS, LS; USDA 6-8, except as noted. From northern China and Japan. Compact, rounded shrub to 56 ft. tall and 4 ft. wide, with oval leaves to 1 14 in. long. Fragrant, lavender-pink blooms appear in 3-in.-long clusters. Resists mildew. Best-known variety 'Palibin' is slow growing, with dense, twiggy growth to 35 ft. tall and wide. It blooms when only 1 ft. high; a profusion of reddish purple buds open to fragrant, single bright pink flowers in 5-in. clusters.
Several popular hybrids resulted from crosses involving S. m. 'Paliban'. 'Jose' (US, MS; USDA 6-7) grows 6 ft. tall, 5 ft. wide, with small, fragrant, lavender-pink blooms produced in spring and then occasionally throughout the growing season, often with a second flush of bloom in fall. 'Bloomerang' (US, MS, LS, CS; USDA 6-9) is another reblooming lilac; it grows just 34 ft. high and wide, with a profusion of light purple or reddish purple flowers in spring and late summer or fall. 'Tinkerbelle' (US, MS; USDA 6-7), a dense, upright grower to 56 ft. tall and wide, has fine-textured foliage and spicy-scented pink flowers; makes a nice specimen shrub or informal hedge.
S. x persica. PERSIAN LILAC. Zones US, MS; USDA 6-7. Graceful, loose form to 6 ft. high and wide; leaves 212 in. long. Many clusters of fragrant, pale violet flowers appear all along arching branches. 'Alba' has white flowers.
S. x prestoniae. PRESTON LILAC. Zones US, MS; USDA 6-7. Group of extra-hardy hybrids developed in Canada. To 12 ft. tall and wide. Flowers come on new growth at the end of the lilac season, after S. vulgaris has finished. Bulky, dense plants resemble S. vulgaris, but individual flowers are smaller and are not as fragrant. One of the best is 'James MacFarlane', a pink-blooming selection that blooms well as far south as Atlanta.
S. pubescens microphylla 'Superba' (S. microphylla 'Superba'). Zones US, MS, LS; USDA 6-8. Selection of a lilac native to China. Compact grower to 7 ft. tall, twice as wide. Mildew-resistant leaves to 2 in. long, with bronze fall color. Deep red buds open to fragrant, single bright pink flowers. May rebloom in early autumn. Heat tolerant.
S. pubescens patula 'Miss Kim' (S. patula 'Miss Kim'). Zones US, MS, LS; USDA 6-8. Selection of a lilac from northern China and Korea. Dense, twiggy, rounded; eventually to 89 ft. high and wide, but stays small for many years. Sometimes grafted high to make a standard tree. Purple buds open to very fragrant ice-blue flowers. Leaves are 2412 in. long; may turn burgundy in fall. Heat tolerant.
S. reticulata. JAPANESE TREE LILAC. Zones US, MS; USDA 6-7. From Japan. To 30 ft. tall, 20 ft. wide; can be grown as large shrub or easily trained as single-stemmed tree. Smooth, glossy, red-brown bark. Leaves to 5 in. long. Blooms on new growth late in the lilac season, bearing white, musky-scented flowers in showy clusters to 1 ft. long. This is the most problem-free lilac. It makes a good lawn tree, street tree, or informal screen. 'Ivory Silk' is a compact grower to 20 ft. tall, with cream-colored flowers borne in profusion even at a young age. 'Snowdance' is slightly smaller, with large panicles of white blooms. 'Signature', to 25 ft. high, has rounded clusters of white flowers.
S. vulgaris. COMMON LILAC. Zones US, MS, LS (some); USDA 6-9. From eastern Europe. Can eventually reach 20 ft. tall, with nearly equal spread. Suckers strongly. Prune out suckers on grafted plants (no need to do so on own-root plants). Dark green leaves to 5 in. long. Blooms in midspring, bearing pinkish or bluish lavender flowers in clusters to 10 in. long or longer ('Alba' has pure white flowers). Fragrance is legendary; lilac fanciers swear that the species and its older selections are more fragrant than newer types. Make excellent cut flowers.
Selections, often called French hybrids, number in the hundreds. They generally flower a little later than the species and have larger clusters of single or double flowers in a wide range of colors. Singles are often as showy as doubles, sometimes more so. All of these lilacs require 2 to 5 years to settle down and produce flowers of full size and true color. Here are just a few of the many choice selections: 'Andenken an Ludwig Spth' (reddish purple to dark purple), 'Charles Joly' (double dark purplish red), 'Katherine Havemeyer' (lavender-pink), 'Madame Lemoine' (double white), 'Miss Ellen Willmott' (double white), 'President Grevy' (double medium blue), 'President Lincoln' (Wedgwood blue), 'President Poincar' (double two-tone purple), 'Sensation' (deep purple to wine-red with white picotee edge), and 'William Robinson' (double lilac-pink).
Other hybrids include 'Krasavitsa Moskvy' ('Beauty of Moscow'), with large clusters of pink buds opening into white double flowers; 'Nadezhda' ('Hope'), with deep purple buds opening into lilac-blue double flowers; and 'Primrose', with pale yellow blooms.
Descanso hybrids, developed to accept mild winters, perform well in the Lower and Coastal South. Best known is 'Lavender Lady'; others include 'Blue Boy', 'Blue Skies', 'Chiffon' (lavender), 'Forrest K. Smith' (light lavender), 'Sylvan Beauty' (rose-lavender), and 'White Angel' ('Angel White').
Provide well-drained, neutral to slightly alkaline soil. If your soil is strongly acid, dig in lime before planting. These plants typically bloom on wood formed the previous year, so prune just after flowers fade. (Until plants are established, just pinch back any overlong stems.) Remove spent blossom clusters, cutting back to a pair of leaves; growth buds at that point will make flowering stems for next year. Renovate old, overgrown plants by cutting a few of the oldest stems to the ground each year. For the few types that bloom on new growth, prune in late winter, before new growth starts. Major insect and disease problems include borers, scale, and powdery mildew.
blossom clusters, cutting back to a pair of leaves; growth buds at that point will make flowering stems for next year. Renovate old, overgrown plants by cutting a few of the oldest stems to the ground each year. For the few types that bloom on new growth, prune in late winter, before new growth starts. Major insect and disease problems include borers, scale, and powdery mildew.