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Cut summer lilacs: When and how much? That is why you should cut out withered to extend the flowering period

Like many other woody plants, summer lilac is traditionally pruned in the spring. But also in the summer, after the end of the flowering period, a nurturing pruning is possible. Learn when and how much you should prune the summer lilac to extend the blooming season.

Pruning summer lilacs: When and how much?

Butterfly lilac clean out in summer instructions

Its flowers attract the eyes and make it a highlight in the garden: the summer lilac. No wonder the shrub enjoys such great popularity. With good care, the flowering period of the shrub extends from July to September. However, to ensure that it continuously forms new panicles during this period, you should regularly remove the faded from the butterfly bush .

Clean out flowering summer lilac: when to remove the panicles?

Cut butterfly bush Remove wilted flowers Extend flowering time

Do not wait to remove flowering. Because as soon as you do, the plant will form new flower buds. In order to marvel at a splendor of flowers, you should clean out the summer lilac once every 10 days. Cut all faded flowers three – to four times a month, so you can extend the flowering period.

A longer blooming period is also environmentally friendly, because the beautiful shrub not only pleases the eye, but provides food for insects in late summer and fall. However, if you do not clean out your shrubbery, you will soon notice that it blooms only once.

There is another important reason to cut off the flowers regularly . Summer lilac self-seeds, and in the flowers are very many seeds. If you do not cut off withered flowers, then the next year you will summer lilac in other places in the garden. But if you regularly cut off the flowers, then the seeds can not form completely. However, you can leave one or two panicles in the fall because the seeds provide food for birds.

To be on the safe side, you should dispose of with the household trash. It is best not to compost or use as mulch. Also, don’t just leave them around the shrub; carefully collect and dispose of all wilted flowers. Otherwise, you risk spreading summer lilac in your yard, your neighbor’s yard, or outdoors. Since it is an invasive exotic plant, it is better to prevent this spread.

Care pruning in summer and autumn: how much to cut the summer lilac?

Summer lilac in the garden extend flowering ideas

In the summer, during the flowering period, that is, July and August, the following caring measures are recommended:

  • Cut off wilted leaves and flowers every 6 to 10 days (it is best to check the summer lilac once a week for wilting). Trim the panicles, including stems, to the nearest leaf axil with sharp, clean secateurs.
  • Also remove any diseased shoots and any leaves that are too close to the ground.
  • The best time to do this is early in the morning or late in the afternoon. Pruning wounds can burn, especially in hot weather.
  • Choose a sunny or cloudy day. Do not cut the flowers when it rains. Water the plants at least one day before pruning. Pruning wounds are open entry points for fungi, and moisture can encourage this.

In autumn, you can rejuvenate the plant. Pruning is carried out at the end of the flowering period. This measure is to bring the bush into the desired shape and eventually thinning. In this case, the shoots are not cut off close to the ground, but only slightly shortened. Never cut them into the old wood. It is best to shorten the old shoots by a third, you can also leave this year’s wood. Cut the shoots to the second leaf axil at the most. The cut should be as clean as possible, so always use sharp loppers.

Care for summer lilacs during the flowering season

Cut off wilted flowers to stimulate flower formation


Outdoor shrubs can cope with little care. In this case, it is sufficient to work compost or horn shavings into the soil once at the beginning of the season.

However, if it is a potted plant, then regular fertilizing is very important. You can use a commercial liquid fertilizer. It is best to take mineral fertilizer and administer it once a week.

Watering should be done similarly – water potted plants regularly so that the potting soil does not dry out. Outdoor shrubs, on the other hand, need watering only during prolonged periods of heat.

Summer lilac is a beautiful shrub that pleases the eye all summer long with its fragrant flowers and green leaves. However, in order for the shrub to bloom from July into the fall, proper care is crucial. This includes regular pruning out of the faded flowers, as well as the nurturing rejuvenation pruning in September. Potted plants are more sensitive to pruning in this process and need more time to recover. They also need watering and fertilizing.