The summer lilac, also called butterfly bush or butterfly bush, is very popular in German gardens. These colorful flowering shrubs attract butterflies with their nectar. We will explain how to properly cut summer lilac and what pruning mistakes to avoid.
The once exotic summer lilac (Buddleja davidii) has already conquered countless hearts of hobby gardeners. Its success is due to the abundance of flowers that attract butterflies in droves. In order for the shrub to bloom again and again every year, a pruning is required from time to time. Although this is not absolutely necessary, it can encourage lazy specimens to make new efforts. In addition, butterfly bushes grow very luxuriantly. In order to keep them smaller, regular pruning is therefore essential. A rejuvenating pruning works wonders, especially for dead summer lilacs.
Since butterfly bushes have a strong need to spread, it makes sense to remove faded flowers in good time.
When is the summer lilac pruned?
- Late Winter or Early Spring: Rejuvenation Pruning
Prune your buddleia in late winter or early spring. At this point the lilacs are not in the sap and no birds or other creatures nest in the branches. A cut in February on a frost-free day is ideal. In late winter, you can also radically rejuvenate your summer lilac and plant it on sticks.
- In autumn: possibly shorten
You can also prune your buddleia in autumn after flowering. However, you should not proceed as radically as with the winter cut. You should only make minor changes, for example if the bush needs to be shortened.
- In late summer and autumn: remove faded flowers
It is important to remove faded flowers in late summer and autumn. The flowering time of the plant is between July and September. Butterfly bushes produce copious amounts of seeds - miss the dried up onesCut off the flowers and you'll soon have lilacs everywhere.
How to cut the buddleia correctly
Butterfly bushes are very fast-growing and extremely easy to cut. So you can't go far wrong with a pruning. Even if you want to go more radical, you don't have to give up the flowers that year. In any case, these only appear on the one-year-old shoots, which only develop after the cut.
- Rejuvenation: Buddleia can be pruned radically without hesitation - even annually. Leave the last 20 to 30 centimeters of the plant and always cut just above a bud or a leaf axil. It is essential that you use sharp and clean tools so that there are no entry points for pathogens and the wounds can heal quickly. You should always cut at an angle so that the water does not stand on the cutting edge.
- Pruning off faded flowers: Once the flowers have faded, it is worth removing the inflorescences before seeds form. Otherwise, it can happen that the butterfly bush spreads quickly in and around the garden. The young seedlings are quickly removed again, but you can save yourself this work. Simply cut back the withered inflorescences to the nearest leaf axil. If you have removed the faded flowers in time, you can put them in the compost without worrying. However, if ovules are already present, you should better choose household waste for disposal.
The butterfly bush or summer lilac is considered invasive due to its ambitious tendency to spread in Europe. The exotic plant does not stick to garden fences, but instead invades the landscape, displacing native species in the process. But the shrub should not be condemned. The plant was given the name "butterfly bush" because it is a valuable food plant for butterflies and bumblebees due to the long flowering period and the abundance of flowers. So butterfly bushes definitely have added value for the insects. Nevertheless, it is advisable to prevent uncontrolled spread, for example by cutting off the withered flowers. There are also sterile varieties, but these are also worthless for insects.
Of course, there are numerous other food plants for insects. If you would like to do something good for the winged pollinators, you will find a selection of insect-friendly plants here. But you can also use insect-friendly seed mixtures such as the Plantura Butterfly Club. This offers butterflies and caterpillars a rich supply of food.