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Propagate summer lilac in water and seed pot: How to succeed in summer propagation by seeds and cuttings.

It blooms all summer long and delights the eye of the amateur gardener with its purple flower buds: the butterfly bush is a real eye-catcher in the home garden. The attractive shrub is easy to care for, and propagation via seeds, cuttings or wood cuttings is also straightforward. We explain how you can propagate the butterfly bush and what you need to bear in mind.

Propagate summer lilac: What are the variants?

Propagate butterfly bush in late summer and autumn instructions.

Basically, there are three variants of how you can propagate summer lilac. You can propagate the butterfly bush from seed. Although this is actually the simplest variant, there is no guarantee of success. The butterfly lilac germinates slowly and the young plants differ from the mother plant. Therefore, propagation by cuttings in water is preferred by most amateur gardeners. It is also very simple and the probability that you will have a young plant the next year is higher.

How to grow butterfly bushes from seed

Propagate butterfly bush by seed how when

Propagation by sowing is very simple: in most cases, the shrub practically sows itself. You just need to give him the opportunity, that is, do not cut off all the fruit capsules. Leave two-three, they will then open at the end of summer and release the seeds ready for harvest.

Sowing is not always successful, and the daughter plant will be different from the mother plant. These differences vary by cultivar. However, Buddleja alternifolia is the easiest to preplant. You can simply harvest the seeds in early mid-August to early September and let them dry overnight on newspaper. Store the seeds in airtight, opaque containers in a cool place indoors. After the spring permafrost is over, you can preplant the seeds in a seed tray and move them outdoors. Use nutrient-rich growing soil. Summer lilac is a light germinator, so cover the seeds only lightly with potting soil. Water them regularly. The seeds germinate very slowly, so patience is needed. After the seedlings sprout and form at least one pair of leaves, you can plant them in the garden.

Propagate summer lilac by cuttings in water.

Propagate summer lilac by cutting cuttings

Late summer and fall is the right time to propagate butterfly bush lilac via cuttings. Cuttings should be between 7.5 inches and 10 inches long and have no flowers.

Woody and soft, young, grass-green shoots are unsuitable. It is best to choose branches from the previous year – they can be identified by their dark green color.

Step-by-step instructions:

Cut the shoots at an angle, because the larger the cut surface, the faster the cuttings will form new roots. Use sharp secateurs for the cleanest cut possible without bruising.

Propagate summer lilac by cuttings cuttings instructions


Remove all leaves, fill jars with lukewarm, decalcified tap water. Wrap a dark, non-transparent fabric or black foil around the jars.

Put some root activator on the cut surface of the cuttings and put them in the water. Change the water three times a week and always add a pinch of root activator to the water. After two to three weeks you will notice the first fine roots. Then it’s time to plant the cuttings in growing pots with a diameter of 10 cm.

Mix potting soil with coarse-grained building sand or clay and fill the substrate into the pots. Then you can put the seedlings.

The cuttings will feel at home on a sunny windowsill. Sunlight promotes growth, root formation and, most importantly, resprouting. If the cuttings form new leaves within the next week, then you can be planted in the garden after the end of the permafrost.

Butterfly bush propagation via cuttings

propagate summer lilacs in seed tray let cuttings take root (1)

Propagation via cuttings is actually very similar to the variant with cuttings. However, there is one important difference: cuttings are placed in water jars without foliage and form their root system there. Cuttings retain a pair of leaves and are placed directly in growing soil.

Step-by-step instructions:

Leave only one or two pairs of leaves on top, cut off all lower leaves. For the growing itself, you can use both growing pots and a seed tray.

In garden centers you can find special growing soil, but you can also make it yourself. For this purpose, mix loose garden soil with organic compost and coarse-grained building sand in the ratio 1 : 1 : 1. Line a baking tray with baking paper and bake the finished substrate for about an hour at 140° Celsius. Then you can pour it into the seedling pots.

Put the cuttings into the pots, water them generously, tie the pots together and cover them with transparent packing film.

summer lilac propagate how and when


Ventilate the pots or the seed tray once a day and water them as needed. The soil should always remain moist. If you notice new leaves after a few weeks or if the cuttings sprout again, then they have formed the root system.

Remove the protective film. The young shoots can spend the winter on the windowsill, in the greenhouse or conservatory and may only in the spring in the garden.

The butterfly bush is a beautiful, splendidly flowering shrub . Propagation is very simple. You can pre-grow the summer lilac via seeds, propagate by cuttings in water or even cut cuttings and plant them directly in growing pots.