When the scent of lilacs hangs on the air, summer is just around the corner. The wonderful smell is warm, almond-like, with a hint of spice, and it floods from the generous flower panicles of common lilac (Syringa vulgaris) in May and June. This large deciduous shrub (which can be grown as a small tree) is hardy, low-maintenance, and very much back in fashion, having fallen out of favour.
Most species of lilac (Syringa) hail from the mountains of Asia, but the main garden form, S. vulgaris, is native to the Balkans. The Greek syrinx means pipe, and one of the common names is pipe tree because syringa stems were once used to craft smoking pipes. The more beautiful word lilac comes from the Persian for bluish: nīlak, after its glowing purple-blue blooms.
In 1563, the Flemish herbalist and diplomat Ogier Ghiselin de Busbecq introduced S. vulgaris to Europe, having brought it to Vienna from Istanbul. Seven years later, he took it to France, where it would undergo its most important transformation. Of the 2,000 or so varieties of S. vulgaris, over 200 were bred by three generations of one French family: the Lemoines. The first, Victor Lemoine, created many superb plants, including the peony ‘Sarah Bernhardt’ and the mock orange ‘Manteau d’Hermine’, but he is most celebrated for his lilacs.
Marooned in his home in Nancy in northeastern France in 1870, during the Franco-Prussian war, he set about crossing single-flowered varieties of S. vulgaris with a double-flowered form that was growing in his garden. Because the shrub was tall and his eyesight was poor, his wife, Marie-Louise, was obliged to do most of the work: perched atop a ladder, while he gave instructions from below, she brushed the flowers with pollen. The joint effort was a success, and the first sumptuous double-flowered garden lilacs were born. Over the years, Victor introduced 64 hybrids – most of them double and all richly scented. Their son, Émile, bred a further 140, and his son, Henri, created 10. Collectively, they are known as the French lilacs and include many of the most covetable varieties.
The lilac varieties to grow
The three most widely available forms of common lilac were bred by the Lemoines: ‘Madame Lemoine’ (white), ‘Charles Joly’ (wine purple), and ‘Katherine Havemeyer’ (pink lavender). All are excellent plants with charming double flowers. However, if you fancy hunting down a lesser-known form of S. vulgaris and to avoid the horror of purchasing a lilac that has been grafted onto privet, it is well worth buying from a specialist supplier, such as The Gobbett Nursery. Plants grown on privet are not as hardy and can be tricky to rejuvenate if they become leggy.
For pure-white double blooms, consider the glorious ‘Souvenir d’Alice Harding’ or ‘Monique Lemoine’, both bred by the Lemoines. ‘Krasavitsa Moskvy’ is another marvellous choice, producing double white flowers from shell-pink buds; it was bred by Leonid Kolesnikov in the 1970s, using – unsurprisingly – Lemoine hybrids.
White lilacs are elegant in urban gardens, by day and by moonlight. Also splendid at twilight are the pale-lavender and blue Lemoine doubles, such as ‘Président Grévy’ and ‘Leon Gambetta’. These traditional shades work well in a country garden, as do pink Lemoine doubles, including ‘Montaigne’ and ‘Émile Lemoine’.
The rich-red forms of S. vulgaris (such as Kolesnikov’s single-flowered ‘Znamya Lenina’) are harder to blend into the garden, being such a bold colour. But their intensity can be softened by planting them alongside silver foliage.
Unusual lilacs to know
S. vulgaris is the ultimate garden lilac, but if you fancy trying a more unusual syringa, there are many fabulous forms to choose from. In a small garden, the Korean lilac S. meyeri ‘Palibin’ has cones of tiny lavender-pink flowers and, reaching only 1 to 1.5 metres, makes a good low hedge, compact shrub, or pot plant.
A little taller at 2 metres, forms of S. pubescens (especially sugar-pink ‘Superba’ and pale-lavender ‘Miss Kim’) and white Persian lilac (S. x persica ‘Alba’) are splendid back-of-border shrubs. Bigger still, the Rouen lilacs (S. x chinensis) are the offspring of S. vulgaris and S. x persica. Capable of 3 metres, pink-purple S. x chinensis ‘Saugeana’ is best in a large garden or as hedging. S. x josiflexa ‘Bellicent’ is a similar size and produces lovely drooping plumes of clear-pink flowers.
These alternatives may lack the buxom hurrah of the Lemoine S. vulgaris hybrids, having much smaller flowers and leaves, but they boast spicy scents and make interesting and attractive garden shrubs.
How to grow lilacs
Lilacs like sunshine and elbow room in neutral to alkaline soil that is fertile and extremely well-drained. The drainage and nutrition of most soils can be improved with the addition of organic matter (such as peat-free compost), as well as sand or grit. But dense clay is not suitable. If you’re on clay, create a raised bed, using humus-rich loam mixed with sand and gravel. Greedy lilacs love an annual mulch of compost and, if your soil has an acid pH, throw in a handful of lime as well.
Pruning boosts flower power and health: after flowering, remove diseased, weak, and dead stems and reduce branches by up to one third. In the long-run, keep S. vulgaris around 2.5 metres. To rejuvenate a mature shrub, prune it gradually year by year, rather than doing one drastic haircut.
Lilacs are a bit dull when not in bloom, but the larger forms can be livened up by sending a climber through them. Viticella clematis (such as 'Madame Julia Correvon’) are ideal – flowering from July into September, they ensure your lilac bush looks beautiful for months.
