Lilac – planting and care

The common lilac is well-known to most, but there are also newer varieties that don’t spread as quickly. Purple, white, pink, or blue? Single or double flowers? Upright or hanging flower clusters? The selection is vast, and there truly is a variety for every garden.

For a small garden, the dwarf lilac can be a good choice. The pink varieties ‘Palibin’ and ‘Tinkerbelle’ or the dark purple ‘Bloomerang dark purple’ often make beautiful ornaments in the garden.

All lilacs are beautiful in their own way, but it’s worth considering a few things in addition to their appearance when choosing a variety:

• Think about blooming time
  Perhaps you can plant several varieties that bloom at different times to extend the lilac season?
  
• Check the hardiness zone
  Choose a lilac that can withstand the climate. If you live far north, you should opt for one of the more hardy lilacs; there are varieties that can survive up to hardiness zone 7.

• Lilacs thrive best and produce the most and finest blooms when planted in the sun. In partial shade, there will be fewer flowers.
  
• The planting hole should be about half a meter deep, and the soil can be mixed with some manure. Grab your spade! A hole that's too small can cause water to stagnate, leading to poor oxygen supply.
  
• If you want to plant lilacs as a hedge, you can plant 3-4 plants per meter.
  
• As with all newly planted plants, it’s important to keep an eye on watering until the roots have properly established themselves.

Photo: Liselotte Roll

The lilac is quite hardy, but it can become a bit sparse at the bottom after a couple of years. Pruning or rejuvenation pruning is necessary if you want to maintain a dense hedge or shrub.

When the lilac has grown unruly and become sparse at the bottom, you can prune the entire shrub down to a few centimeters above the ground in the transition between winter and spring. This will encourage the shrub to produce new shoots. The downside is that you are starting over, and you will have to wait a few years before the lilac grows large again and blooms.

To rejuvenate the shrub is a better method if you want to keep the lilac high and dense over time. Select some of the oldest and thickest branches, about every fifth one, and cut them down to a few centimeters above the ground. But don't remove too many, as strong branches are necessary to give the shrub stability. Some thinner branches can also be cut at various heights. New, green shoots and leaves will grow where you cut and fill out the shrub.

With this thinning method, you can keep the lilac high and dense. The branches that are cut will not bloom the following year, but since you still have older branches, there will still be flowers on the shrub. Once the shrub has reached the desired height, you can maintain it by trimming the tall branches to an angle. This can be done annually.

TIP! If you fertilize with natural fertilizer inside the hedge, the root shoots outside will be fewer.

Photo: Liselotte Roll

If you want your lilac to become a small tree instead of a bush, simply let it grow while removing the shoots that get in the way. Over time, the trunk will become more and more bare at the bottom, and when the tree gets older, you can annually remove dead branches and shape the crown. As long as you cut into live wood, the lilac will produce new shoots and leaves.

Note that so-called "noble lilacs" are often grafted onto a common lilac rootstock. If you prune too hard or too far down, you risk getting new shoots from the original lilac rather than the noble variety.

This is not strictly necessary, but if you remove the faded flowers, you’ll get rid of the brown, sad remnants, and the blooming will look more beautiful the following year.

Many lilacs send out root shoots. These can easily be dug up and planted elsewhere in the garden. Choose some that are about half a meter tall, and plant them directly in the ground or in a pot with moist soil where they can stay until the root system has become larger. When you plant the new lilac in the garden, you can cut the shoot a few centimeters above a pair of leaves – this will make the plant focus its energy on the roots instead of the leaves.

Find your favorite among our lilacs

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