Few plants evoke the nostalgia and fond memories that Lilacs bring forth, both in sight and scent.  Lilacs are special among the special, and no garden should be without at least a token specimen. 

Lilacs have been around since the 1700's. George Washington and Thomas Jefferson both grew lilacs in their gardens.  Individual plants can live for hundreds of years, so the plants you put in the ground today may still be enjoyed by your grandchildren and great grandchildren in the future.   

Lilac colors are the quintessential essence of spring.  Varying shades of purple, pink, white,  yellowish, light blue, red, and bi-colored lilacs can be readily found at garden centers or online.  Sizes of mature plants vary, so virtually anyone who wants to try their hand can find a variety suitable for their site.  Mature plant heights vary from about 4 to 15 feet.  Lilacs are very cold-hardy plants, and there is a good selection of plants all the way to zone 2 in the north.  For southern gardeners, a few varieties, most notably Lavender Lady and Miss Kim will make you proud to zone 7.  In zone 8, look for Cutleaf Lilac with its pale lavender flowers.

For all the well-known virtues, there are a couple of minor drawbacks to gardening with lilacs, but in my opinion they are not enough to preclude having this plant in the home landscape.  The first is that Lilacs are relatively short bloomers, with most blooming for only 2-3 weeks in the spring.  By carefully choosing several types of Lilac by bloom time  and planting them in close proximity, the blooms of Lilacs can be enjoyed for up to 6 weeks in the spring for those who just love the far-reaching fragrance and spring-like colors of these beautiful plants.  One other big drawback is that many Lilacs are very susceptible to powdery mildew, which is usually not a lethal disease, but does make the plant look fairly sickly when it strikes. Strategies to prevent powdery mildew include spacing the plants properly to allow for good air circulation, providing adequate sunlight, and removing dead leaves in the fall.  Varieties of Lilac have been developed that are resistant to powdery mildew, and obviously they are preferred for new plantings if they meet the desired qualifications for fragrance and bloom color.

Lilacs belong to the Olive family, and cousins include jasmine, forsythia, and olive trees.   Established plants bought from the garden center should be planted in the fall for the best survival rate. In a pinch, you can try planting in the early spring and if you meet all the requirements, your plant will probably do all right, but don't expect it to bloom that year.  Choose a sunny location (the more sun, the better) and dig a hole slightly larger than the root ball in a well-drained location. Add a bit of 20-20-20 fertilizer to the hole before planting your Lilac.   Place the plant 2-3 inches deeper than it was originally planted at the nursery, but no more than that.  Backfill the hole and water in until the soil is level all the way around, then add mulch with straw, hay, leaves, or whatever you have handy.  If planting multiple specimens, space no less than 5-6 feet apart.  Lilacs will do fine in most soils, but do prefer a neutral or slightly alkaline soil.   If you happen to be in an area with acid soil such as New England, add some bone meal to the hole at planting time to sweeten the soil.

Lilacs take a couple of years to become fully established and they may not bloom the first year.  However, once established, they can last for centuries, as mentioned above.   Established plants  are very drought tolerant and rarely need supplemental watering.  Weeds should not be a problem with proper mulching, but if weeds do appear, remove them by hand and add more mulch.  Never cultivate around the base of your Lilac.  Remove withered blooms as soon as possible to direct the plant's energy into blooms for next year.  Lilacs don't need extensive pruning, so don't prune your new Lilac for the first few years, and after that only prune to retain the plant's shape.  Pruning should be done as soon as possible after flowering, so don't delay.  If you wait too long, pruning will remove next year's flower buds and the plant will not bloom at all. 

Lilacs can be propagated by seed, but this is not recommended, as the seedling will probably not be true to the parent plant, as most Lilacs are hybrids.  However, if you are adventurous, you should know that the seeds need stratification (a period of cold) to sprout, and can be planted directly into pots or into the ground in the fall for sprouting the next spring. 

Many Lilacs sent out root suckers that can be dug in the fall and transplanted to another area of the garden.  This is the easiest and best way for the average gardener to multiply his Lilac population.  It will take these suckers about three years to become a viable addition to the garden, but again, once established they will last a lifetime.

Lilacs can also be layered and grafted for propagation purposes, but this takes a bit of knowledge and several years to achieve, and most home gardeners would probably be better off just going to the garden center and buying a new plant or propagating the old one via root suckers. 

Companion plants for Lilacs include many spring flowering bulbs, such as Hyacinth, Daffodil, Tulip, Grape Hyacinth, and Crocus. Pansies in a contrasting color work very well, as does Hosta, or you could try a short ornamental grass as a nice year-round understory plant. 

Lilac blooms make wonderful cutting flowers, as depicted in the picture above, but they won't last long unless you harvest them properly.  Cut the stem early in the morning when the water content is the highest.  Mix 8 ounces of warm water, 8 ounces of clear soda such as 7-Up, and 1 teaspoon of bleach in a vase, and submerge the stems.  This provides the cuttings with all the nutrients they need, with the bleach preventing bacteria build-up.  Cuttings done in this manner will last up to a week in the vase. 

Lastly, Lilac blooms are edible. They have a floral, slightly bitter taste, and can be candied for cake or pie decorations like Violet blooms (See Violets for specific instructions), or added fresh as garnishes to salads and desserts. 

More information on Lilacs is available in the Gardening QA Section.  Click here to see what other gardeners are asking.