So beloved are lilacs that they were one of the first plants that early settlers brought to America. Nothing can top the lovely fragrance of lilacs as spring begins to slip into summer. Lilacs are so hardy and easy to grow that they often persist for hundreds of years after the person that planted them is gone. While considered old-fashioned by some, lilacs are one of the most planted landscape shrubs in North America.
Lilacs are originally from colder areas of Asia and Europe. They do well in Zones 3 to 7. There are also varieties of lilacs that will do well in Zones 8 and 9. Most lilacs grow as large shrubs. Some varieties of lilacs, however, grow as small trees, with a single trunk, and there are dwarf varieties on the market for those who have small yards. Most lilacs have dark-green, heart-shaped leaves. Lilac flowers range from lilac to deep wine-red, white and light yellow. The flowers are born in large clusters in late spring. Most lilacs have that wonderful lilac scent, but beware: some varieties have little or no fragrance. Lilacs bloom for only a short time, so to prolong the heavenly scent, you can plant several varieties that bloom at different times.
Choose the site for your lilacs carefully as they resent being transplanted. Although they root easily, they may not bloom for several years after being moved. Lilacs need full sun for the best blooms and disease-resistance. They prefer light, sandy soil that is slightly alkaline and well-drained. They may not bloom well if the soil is too acidic and may fail to grow in heavy, wet soil. Lilacs can get 15 feet high and wide, so make sure the spot where you plant them will be big enough for their adult size. If you are using lilacs as a hedge or screen, plant them 6 to 10 feet apart.
Transplant lilacs in a cool period of the year; early spring, before they leaf out, is ideal. Keep them watered while they get established. Too much nitrogen will cause lilacs to have lots of leaves and few flowers,. Use a little 5-10-10 fertilizer in the early spring if the plant seems to need a boost.
Lilacs sometimes get powdery mildew, a fungal disease that makes the lilac leaves look like they were dusted with white powder. While it looks bad, it doesn't affect the lilac plant too much. You can use a garden fungicide as a preventative spray once the weather starts getting warm. Another problem of lilacs is Lilac Borer. If lilac stems seem to be wilting, check them for tiny holes. This usually affects older, woody stems. If you find holes, trim that stem off as close to the ground as you can and destroy it. Pruning the oldest stems off lilacs helps prevent Lilac Borers from being attracted to your bush. You can also treat the lilac with a systemic insecticide to kill borers.
Lilacs bloom on old wood; the blooms form on stems that grew the year before. Too much pruning at the wrong time will leave you with no flowers. Prune lilacs immediately after they flower. If the bush is too large and overgrown, take out the largest and oldest stems first, the ones with woody bark. Unless you need a drastic pruning to restore order, don't remove more than 1/3 of the plant at a time. You can trim the tops back to a more manageable height, but you may not have many blooms the next year. Most shrub lilacs sucker from their root system. Remove suckers that are spreading too far into other areas. They can be dug and transplanted to start new lilacs. All lilacs benefit from removing the dead blooms so they don't form seeds.
There are hundreds of varieties of lilac. If you like the look of old-fashioned lilacs, choose common lilac, Syringa vulgaris. Some popular varieties include Lilac Sunday (typical lilac color but many more flowers), Charles Joly (double flowers of dark purple-red), Rochester (white), President Lincoln (blue), Krasavitsa Mosky (double flowers of pearl pink), Primrose (pale yellow), James Mcfarlane (a late-blooming pink) and Sensation (a violet red with white edge). Dwarf and compact varieties include Miss Kim (late-blooming lilac color), Tinkerbelle (deep pink) and Red Pixie (wine red). Lilacs for warm climates are Angel White, California Rose, Dark Knight (deep purple) and Lavender Lady. Tree lilacs are often sold as Chinese or Korean tree lilacs. Most tree lilacs have creamy white flowers, but Syringa meyeri has red-purple blooms.
Tree lilacs make excellent specimen trees as they have interesting bark and fall color as well as flowers. The large bush lilacs make good privacy screens and hedges. Dwarf and compact varieties can be used in foundation plantings and in perennial beds.
Lilacs make excellent cut flowers and the flowers can be used to brighten spring salads.
The pussy willow is loved by children and is often used in spring floral arrangements, both dried and fresh. The pussies are actually the male flowers, called catkins, which open in early spring before the leaves appear.
Blue Mist, Bluebeard, Blue Spirea or Caryopteris--whatever you want to call it, this delightful late-summer bloomer is a magnet for butterflies and a big asset in the late-summer border. Caryopteris has true blue flowers and is hardy, tough and easy to grow.
Learn how to cultivate Leucothoe fontanesiana, the Rainbow Fetterbush.