Lilac or Syringa

Most lilacs are not very graceful; they get tall and leggy, and their leaves re a magnet for mildew in late summer. But their fragrant flowers redeem them, and they will always be a favorite with gardeners. The common lilac (Syringa vulgaris) is the one most often grown. It has spawned hybrids by the hundreds in shades of lavender, purple, rose and white. It is very hardy and seen it grow as tall as 20 feet.

 

The adventurous can experiment with other lilac species and their hybrids, for different flower shapes and growing habits and to stretch out lilac time to as much as six week. The early Korean lilac (S. oblate dilatata) is fairly tall and has large, fragrant lilac pink flowers. Cut leaf lilac (S. laciniata) is a short shrub with pale lilac flowers and finely cut leaves. Little leaf lilac (S. microphylla) is also short but very wide; the variety “Superba” has deep pink flowers. Persian lilac (S. x persica) is also very wide and spreading the pale lilac flowers is small but very profuse Meyer lilac (S. meyeri) is short with deep purple flowers.

For late bloom, try late lilac (S. villosa), which has long lilac or pinkish flowers, and Japanese tree lilac (S. reticulate, also called S. amurenesis japonica) which can grow as tall as 30 feet and bears long white flowers in mid June. Most of these are hardy and early Korean lilac is also hardy.

Lilac likes a light, fertile well drained soil with a neutral pH. If you’re acid you might dig in some lime, bone meal and wood ashes. Lilacs are easy to transplant but should not be dug while the new leaves are emerging. The powdery mildew they get is unattractive but generally harmless; scale infestations should be controlled with dormant oil. The loss of branches can sometimes indicate borers in the lower stems look for little holes with sawdust beneath them and cut the stems and burn them.

Prune lilacs only after they have become well established. Remove the oldest stems and let a few new suckers grow up to take their place, but don’t leave too many suckers that can rob the plants energy and reduce the number of flowers. Carefully pinching off spent flowers just to the first leaves can result in more blooms the following year. Old plant can be cut as far back as 4 inches from the ground and still come back as bushy, rejuvenated plants, but this is best done over a period of three years. Cutting back a third of the old stems each time Severe a pruning can be done in early spring before buds swell, lighter pruning just after bloom.

Lilacs in the Spring

Lilac has become one of the most popular of our garden shrubs. The emergence of its sweat smelling blossom in May is a sure sign the summer is just around the corner. Many of the lilacs being grown these days are specially breed varieties that offer a range of flower colors from white, through pink or blue, to deep violet. The original lilacs had pale pinkish violet flowers the color now called lilac.

 

Lilac belongs to that small group of plants that are so familiar in Britain that people mistakenly assume they are native. In fact, most lilac species are native to Asia, with just a few species being found in Eastern Europe. All lilac species are members of the same genus, Syringa, which is itself a member of the olive family. Like other members of this large family, such as privet, ash and forsythia, lilac grows extremely well in the British Isles. One great advantage is that it is tolerant of both acid and alkaline soils. Indeed, on a small scale lilac has become naturalized in this country. The earliest species of lilac to be introduced in Britain and still the one most commonly grown here is the common lilac “Syringa vulgaris”. This species is native to Eastern Europe and Asia Minor. The word lilac comes from the Persian word for bluish lilac or nilak. It was first appeared in Western Europe I the 16th century and was introduced to Britain in 1621 by the naturalist John Tradescant, who later became King Charles I’s gardener.

 

In appearance, the common lilac is typical in many ways of most Syringa species. It is a shrub or occasionally a small tree, growing no higher than 8m. Usually, it it has several stems growing from the base although there may be just a single slim trunk. The bark is smooth and grey. The leaves are mid green, smooth surfaced and have a characteristic heart shape. They are folded along the central vein so that when seen in cross section, they are shaped like a V. The leaves can grow to a length of 15cm.

 

The flowers emerge in May on pyramidal panicles about 15 to 20cm long. On common lilac, the flowers are not surprisingly, lilac colored but on other species of lilac they can vary from white to pink, mauve, blue or deep purple. The panicles may also be much longer on other species, sometimes reaching a length of 45cm. The flowers are followed by the fruits. These consist of flattened capsules that split, each releasing two winged seeds; they ripen in October.

 

Soon after the common lilac reached Britain the first of many lilacs native solely to Asia was discovered. This was the Persian lilac “Syringa laciniata”, named after the country in which western botanists first discovered it growing. In fact, it has been cultivated in both Persia and India for centuries. The Persian lilac in much smaller than the common lilac, rarely reaching more than 2cm in height. It is unusual among lilac in having leaves that are lobed rather like those of an oak. It produces violet purple flowers in May.

 

The Persian and common lilacs were crossed several times in attempts to produce a superior lilac. The most notable success came in 1795, when once Monsieur Varin, the Director of Botanic Garden at Rouen in France, produce a hybrid that was named Rouen lilac “Syringa x chinensis”. This is a handsome shrub, still popular among gardeners. It grows to a height of 4.5cm and bears large compound panicles of lilac colored flowers in May. At this time of the year, the whole bush may be covered with flowers.

 

Moreover, during the 19th century, many more lilac species were discovered and brought back to Britain as botanists began to explore the Far East. The famous plant hunter, Robert Fortune, discovered Syringa oblate growing in a Shanghai garden in 1856. Unluckily it does not flower well in this country because its blossom appears early in the year. Often, a spell of warm weather in early spring induces the flower buds to grow, only for them to be killed soon after by a sudden cold snap.

 

Despite its frequent failure to flower well, S. oblate soon proved itself to be a useful source from which to breed hybrids and varieties. Many of the beautifully colored lilacs grown today are crosses between the common lilac and S. oblate. Much of this work was done by the French horticulturists Victor Lemoine and his son Emile in Nancy during the 1870s’. Several of the far eastern species of lilac resemble small trees rather than shrubs. For example Syringa pekinensis grows to a height of 6m and always has single trunk. In June its spreading branches are covered with a profusion of cream colored flowers borne on small panicles 7 to 12 long. This species was discovered in northern China at the end of the last century.

 

Further, during the 19th century one further species of European lilac was found to place alongside the common lilac. It was discovered in 1830 growing in Transylvania and the Carpathian Mountains of Eastern Europe by the Baroness of Josika. It is now known as the Hungarian lilac “Syringa josikaea”. This lilac is not one of the most attractive but like Syringa oblate, it has proved to be a useful source for hybrids and varieties. Many of the finest modern lilacs were raised from this species by Dr Isabella Preston, who worked in Ottawa, Canada during 1920’s. One of the most popular of her hybrids is Bellicent a large arching shrub with clear pink flowers trusses about 25cm. Which appears in May? Traditionally, lilac used to play an important role in folk medicine, the flowers and bark being used to reduce fevers. Lilac must have made an unpleasant medicine since it has an extremely bitter taste. The wood from a lilac shrub has few commercial uses nowadays, though in Victorian times it was used for decorative inlay work.