Lilac not blooming: Learn what the possible causes are and what you can do about it

Lilac is a very popular shrub for the garden and that's no wonder. It not only impresses with its magnificent, fragrant flowers, but is also quite easy to care for. Once it has grown well and is large enough, the flowers appear to appear all by themselves. But what if the lilac doesn't bloom? Depending on whether it hasn't bloomed at all yet or whether it suddenly doesn't want to bloom anymore even though there were no problems before, the causes can be different. The lilac is not blooming – what are possible reasons? We have listed them for you.

Why isn't my lilac blooming?

The causes of this problem can be different. Most of the time it is due to the wrong location, age or inadequate care. The following list will help you find the cause and do something about it.

The plant is still too young

You have bought a plant and are now waiting full of anticipation for the first beautiful flowers. Well, a plant that is too young cannot bloom yet. In this case there is nothing you can do - you just have to wait and see. Some varieties take up to three years to bloom for the first time. Your lilac offshoot isn't blooming? The shrub probably just needs a while to grow and get used to the location.

Are the site conditions correct?

These pretty busheslike full sun. The more you get of it, the more flowers the plant produces. The soil should not be underestimated either. Unfortunately, there are no uniform conditions here - different varieties prefer different soils. Some people get along wonderfully with lime-rich soil, while others don't like it at all. Therefore, find out about the requirements of your variety.

However, something that all lilac varieties have in common is that they absolutely cannot tolerate waterlogging. So make sure to provide them with well-drained soil.

Is the location rather dark in spring or was therea lot of rain, this also affects whether and how many flower spikes the shrub will produce.

Lilacs aren't blooming this year - what could be the reason?

Has anything changed at the location?

If your shrub has flowered well so far, but not or less so this year, the location cannot be the cause, unless you have changed something. A new roof or privacy screen that suddenly casts a lot of shade can affect flower formation. Other nearby plants may now have grown very large and, above all, interfere with the sunlightTrees with their lush crowns.

The wrong fertilizer

Has nothing changed at the location? Then a nutrient deficiency or even excess would be a possible cause of the flower failing. The latter is the case if you administer too much nitrogen. This promotes the growth of the plant in general, but this has a negative effect on flower formation. Instead, place greater emphasis on phosphorus in an organic fertilizer. Compost is also a wonderful fertilizer for the shrub.

Lilacs do not bloom after pruning

Of course you can trim and shape your lilac bush. However, you should know something important in order to do it correctly. The plant forms its buds the previous year. So anything you remove after bud formation will lack flowers in the spring. For this reasoncut in time, namely immediately after flowering and avoid cutting back too radically if you also value flowers next year.

Larger cuts are only necessary if the plant has become too large and needs to be reduced. But then you assume that you will have to do without the usual blooms the following year. Lilacs only bloom on those shoots that came from the previous year. Otherwise, it is sufficient if you simply remove the spent flower spikes.

The plant is diseased or infected

Diseases can also affect the plant and deprive it of the strength to produce flowers. So it's worth paying attention to that too. A fungal infection can cause flowering to stop. More precisely, it is the so-called lilac disease that leads to this if it is not treated in time.

The infection can be recognized by the following features:

  • brown streaks on the bark
  • Spots on the leaves that appear greasy
  • withering shoots
  • black discolorations

Unfortunately, the only thing you can do is a radical cut. This is done down to the healthy wood. This means that you still won't have any flowers for the next two years, but at least you will save your plant.

Pests also disrupt the formation of flowers and more specifically the larvae of the lilac leaf miner. However, you can combat these successfully with the right protective agent.

Lilacs in pots do not bloom

Is your potted lilac not blooming? This can have the same causes as withBush in the garden. So check the location, the potting soil and the plant for any diseases and prune the plant correctly.