How and when to best propagate your favorite lilac depends not only on the method chosen, but above all on the respective species and variety. Not every variety of lilac can be reproduced in every way - depending on the lilac, certain techniques work better, others work worse or not at all. In this article we provide you with an overview of common methods and the corresponding instructions.
What is the best way to propagate lilacs?
You can propagate lilacs using various methods: cutting off the roots (for wild lilacs), cutting cuttings (for almost all varieties), using cuttings (for Chinese, Hungarian and arched lilacs) or sowing seeds (for your own varieties).
Extra easy. Propagation via root runners
Many lilacs form so-called root runners, which you simply cut off with a spade in spring or autumn and replant in the desired location. It couldn't be easier to propagate lilacs - but it can't be done with all species. You can use the method well with varieties of wild lilac, which form a lot of root runners. Noble lilacs (for example 'Charles Jolie' or 'Souvenirs of Ludwig Späth') can develop runners, but these are of the wild form onto which the noble variety is simply grafted. You can only get true root runners from noble varieties that were bred using the in-vitro process - although experience shows that these only very rarely develop.
Works with almost all varieties: propagation via cuttings
If propagation via root runners is out of the question - for whatever reason - you can cut cuttings from almost all varieties and try rooting. Depending on the type and variety, this sometimes works better and sometimes less well, but it can definitely be tested. Propagation from cuttings works very well with dwarf lilacs (e.g. Syringa x meyeri 'Palibin') or the popular Preston hybrids (Syringa x prestoniae), whereas you have significantly more loss with the more sensitive noble lilacs. You should be successful if you follow this method:
- Cut the shoots or head cuttings during the flowering period in May / June.
- Select unwoody offshoots with at least three leaf nodes.
- Remove the lowest leaves, leaving only two or three.
- Cut the remaining leaves in half.
- Mix the potting soil from lean soil, sand and algae lime (€28.00 on Amazon).
- Fill small pots with the substrate.
- Put the cuttings in there.
- Wet the substrate well.
- Put a cut PET bottle over it as a greenhouse.
- Alternatively, you can also stick shish kebab skewers into the ground
- and put a translucent plastic bag over it.
- The leaves must not touch the plastic, otherwise it will quickly become moldy.
- Place the pots in a bright (but not directly sunny!) and warm location.
- Water and ventilate regularly.
Now it's time to be patient: many lilacs take up to a year to develop roots, so the cuttings often only sprout in the following year.
Rarely successful: cutting wood propagation
If you want to propagate a Chinese lilac (Syringa x chinensis), a Hungarian lilac (Syringa josikaea) or the bow lilac (Syringa reflexa), we recommend the quite uncomplicated propagation using cuttings. However, this method is not recommended for noble lilac varieties, as very few woods actually grow here - depending on the variety, only every tenth to fifteenth actually forms roots. With the species mentioned, however, you can look forward to new young plants after a year. And this is how it works:
- Cuttings are cut in late autumn after the leaves have fallen.
- Unlike cuttings, these may no longer have any leaves.
- Cut annual shoots about the length of a pencil.
- These should have a pair of buds at the bottom and top.
- Tear off a strip about two centimeters wide from the bottom of the bark.
- Place this end in the prepared outdoor bed.
- This should be in partial shade.
- Dig up the soil here thoroughly and enrich it with compost.
- The cutting wood must be about a third or half of the way into the ground.
- Cover the bed with fleece over the winter.
- The following spring you can see which cuttings have grown and which have not.
If you don't have a chance to put the wood in autumn, you can also wrap it in a clean cloth and store it in the refrigerator over the winter. Finally, the planting takes place in the spring.
Provides surprises: sowing lilacs
Many lilacs form capsule fruits after flowering, which you can only let ripen and finally harvest in autumn. Pour out the fine seeds, carefully separate them from other parts of the plant and sow them immediately in a bowl of potting soil. Leave them outside in a shady and cool place over the winter and don't cover them until January. At this time, place them in an (unheated) greenhouse and keep the substrate slightly moist, the seeds will soon germinate. The young plants are first transplanted into pots in spring and not planted outdoors until autumn. Please note that seedling propagation is not varietal and you can often experience surprises. If you want to breed your own varieties, you'll probably have success with this method.
Tip
Noble lilac is often discussed via oculation - i.e. H. the grafting of a shoot on a shoot of the wild species - propagated. In contrast to in-vitro propagation, which is more commonly used in professional horticulture, you can carry out this method yourself at home.
