Busting out in sumptuous clumps of intoxicatingly scented blooms, lilacs are sensational plants. So why are they so unloved? Just Google “lilacs bad luck” and you’ll find all kinds of lore about how bringing lilacs into the house is not good and wearing a sprig of them can be even worse. Then there are the naysayers who say that lilacs can grow too big and lanky. And that, except for their brief burst of beauty in late spring, they are a rather boring bush. Ouch! Here’s how to look at lilacs differently. (Click on any photo for more details.)
Lilacs aren’t native to North America. The most common species found in Southern Ontario gardens is Syringa vulgaris, native to the Balkan mountain regions. No surprise, then, that there are lots of lilacs with names like Taras Bul’ba (above right) or Bogdan Khmelnitski (below left).
Drive down just about any country road in these parts of Southern Ontario and you’ll often find huge lilac bushes growing in what looks like wild abandon. These can be signposts for botanical archeologists. Lilacs were often planted by settlers from Scotland, England, Russia, France near their homes to remind them of the home they left so far behind. The plants were commonly situated just outside the front door or a bedroom window so their lovely scent could be enjoyed to the maximum. If you find a stand of lilacs in the middle of a field today, chances are you’ll find the foundations of an old stone or log farmhouse on closer inspection.
The Royal Botanical Gardens in Burlington, Ontario, has one of the world’s largest collection of lilacs–over 700 varieties. In fact, the RBG is the International Cultivar Registration Authority (ICRA) for lilacs. That means they register new cultivar names. Identifying a cultivar in precise detail includes using a colour chart with 808 hues to accurately determine each flower’s shade. For an excellent overview on lilacs in Canada, where to site them in your garden and how to maintain them for best shape and maximum blooms, go to the Katie Osborne Lilac Garden page in the RBG’s website. This page also has a great read about Preston lilacs (Syringa x prestoniae), a Canadian hybrid of late blooming lilacs that are extremely hardy, bred intentionally for our challenging climate.
Lilacs have a reputation for growing leggy and start to elbow out other plants in a smaller garden. Some plants can grow up to 20′ in height. The best time to prune a lilac is right after the flowers have faded. That’s because next year’s buds start to grow right after this year’s flowers have bloomed. If you wait until later in the year, you’ll be cutting off all those new buds. Here’s an excellent video from University of Maine educator Marjorie Peronto demonstrating how do prune a lilac for best results.