growing and picking lilacs
If you ask people to name their favourite scented flower, lilac is almost always mentioned. But, if so many of us like lilacs, why do so few of us grow them? It's true they can be accused of performing only for a short time, but if you have just a small garden with a hedge, why not put a lilac in there? And you can thread a viticella clematis up through the branches to extend its moment of interest.
Almost every older garden has at least one lilac tree – a purple and a cream or white – yet gardens planted more recently rarely include them.
I've just been to visit Chris Lane, who has a large lilac (Syringa) collection at his nursery near Sittingbourne in Kent. He loves them for their minimal maintenance regime and their incredible performance when the garden is at an in-between stage – spring bulbs are just about over, but summer plants are yet to reach full bloom. If we still like to plant mock orange (Philadelphus), which flowers a month or so later, when the garden is full to the brim with scent and colour, why have we lost our love of lilac? Surely it does much the same thing, but at a more useful moment.
Lilacs do benefit from pruning after flowering to keep them in bounds, so that the fragrance doesn't just waft off to the heavens, but that really is it. Even the pruning isn't a three line whip – just every other year will keep the structure open, promote good air circulation and prevent mildew. Lilacs grow well on almost any soil (but particularly thrive on chalk), in full sun or light shade and are incredibly hardy to low temperatures.
Walking down the great, fluffy, scented pom-pom lines at Chris's nursery (where he also holds a huge collection of wisterias and witchhazels), I picked out one variety in each of the different colour groups that stood out from those around them.
My favourites are the deep, rich purples, the deeper the colour the better, so the S. vulgaris hybrid, 'Ogni Moskvy' won the day for me, but that's now tricky to find. With fewer of us buying lilacs, the range of readily available varieties has shrunk to a third from only 20 years ago and this one is a victim, but 'Congo' or 'Charles Joly' (AGM) are the next best thing. They are not quite as rich and dark but still very handsome and widely available.
One notch down in tone is a species hybrid, S. x hyacinthiflora 'Esther Staley' (AGM), which makes a large shrub with reddish purple buds and mauve flowers. This would look and smell beautiful cut short and arranged with early roses. Paler still in the most beautiful shell pink is another vulgaris hybrid, 'Lucie Baltet', with the buds a slightly deeper shade than the fully open flowers, and the whole panicle very precise and delicate in its habit. Then you can move from the mauve to the pale blues, to the widely available 'Firmament' (AGM) which has been in cultivation and popular since 1932.
In the white to cream range, it's hard to beat 'Maud Notcutt' for a starched linen white, with 'Madame Lemoine' (AGM) standing out as the best white double. This won the vase life trial here, three days longer than the average six. The complexity of the flower makes the doubles more durable on the plant outside as well as when they're cut, but the downside is the flowers stay on the bush as they brown – rather than dropping – so you'll need to deadhead them if you like things tidy.
'Primrose' was the final one I selected, the colour of posh unsalted butter in bud, softening to ivory when fully open and another of my favourites, despite its fainter scent.
As a May and early June cut flower, lilac is invaluable to pick for a good-sized vase inside. I know the old wives' tale that makes people reluctant to bring lilac into the house – it's said to bring bad luck – but most of us can get beyond such superstition. With it, you can fill a room with that soft, sweet perfume.
Cutting tips
To make lilac perform well once cut, you need to know three things. The first is that almost all the leaves should be removed. With their large surface area, they'll be transpiring like billy-o and will need plenty of water to do so, yet they have only a slim stem to absorb it. By reducing the foliage to what immediately surrounds the flowers – which add prettiness to the vase – you make the stem last longer.
The next thing is to sear the stem end for 30 seconds in boiling water. Pour the water from the kettle into a mug and plunge the bottom 10 per cent of the stems into the hot water. Take them out and put them into a bucket of deep cold water and store them cold and dark for a few hours or, better still, over night. Pick, sear, rest, arrange – that's the order to do it. If you pick and immediately arrange, that's when the whole panicle has a tendency to collapse.
The final thing about picking lilac is to grow it so that the stems are at an easily pick-able height. Commercial cut-flower lilac growers coppice or pollard their plants every couple of years, not bothering with careful pruning, but simply taking the main stem down to the ground (or about three feet in the case of the pollard technique). Fewer stems will then form with very little leaf, but the panicles of flowers are huge.
I think lilac is well overdue for a renaissance.
This article first appeared in The Telegraph on 7th June 2013.