The common lilac (Syringa vulgaris) has been growing in German gardens since the 16th century and has enjoyed great popularity ever since: the shrub is considered to be extremely robust, easy to care for and blooms profusely every year with up to 30 centimeter long, mostly purple flowers or white flower spikes. Now the tree can also get quite old and very large - if you have a rather small garden, you have to keep the plant's growth small.
How to keep lilacs small?
To keep lilacs small, you should install a root barrier, prune the bush annually after flowering, remove dead and dead material and eliminate cross-growing shoots. Alternatively, you can plant dwarf varieties such as Syringa microphylla or Syringa meyeri.
Suitable measures for keeping lilacs small
By the way, this not only applies to small gardens, but also to lilacs grown in pots. Here, too, the bushes must be limited in their growth, which is best achieved through these measures:
- Installation of a root or rhizome barrier when planting.
- Annual pruning immediately after flowering.
The root barrier is not necessary for potted lilacs, as the roots are kept small anyway due to the size of the planter. Don't buy the largest pot for young plants straight away, but rather adjust its size approximately every two years depending on the plant's growth. Then it's time for fresh substrate anyway, so you can transplant the lilac into a larger container. For planted lilacs, however, a root barrier is not only useful for reasons of size growth, as many varieties develop very extensive, strong and difficult to remove roots.
Annual pruning – this is how it works
Although lilacs generally don't need to be cut, you should use pruning shears every year to keep them small. Always cut immediately after flowering, as the following year's flower buds are always formed directly after the new shoots. If you cut too late, you may remove the upcoming flower. And this is how you keep the lilac small:
- Remove up to a third of the wood.
- Flowered and dead things must be cut away.
- Also inwards and criss-crossing shoots.
- Short the remaining shoots as desired.
- Superfluous or too large main branches or trunks are removed directly at the base.
Avoid radical pruning, otherwise the lilac could sprout from the roots again - with the result that you are suddenly faced with hundreds of root shoots sprouting from the ground within several meters of the former trunk.
Tip
Instead of keeping a vigorous lilac small, you can also plant a dwarf variety. Suitable examples are Syringa microphylla and Syringa meyeri, which each only grow to around 150 centimeters high.