Not all knotweed is the same: The plant family of the genus Persicaria includes around 30 different species, of which the climbing knotweed (Fallopia baldschuanica) and the carpet-forming garden knotweed (Bistorta affinis) in many different varieties are of particular interest for the home garden. Both types can be propagated in a similar way.

Knotweed is easy to propagate from cuttings

Propagation of different knotweed species

Both types of knotweed can be easily propagated from seeds and cuttings. While sowing is always carried out in spring, propagation takes place via cuttings both in summer and in winter. Summer cuttings should be herbaceous and not yet lignified, they are best grown outside right away. In winter, take woody cuttings instead, which are rooted in a warm place and finally planted out in spring. Propagation by division, on the other hand, usually only works with the groundcover knotweed. The best time for this is spring.

Implement knotweed

In principle, it is possible to dig up and move larger or older specimens, but this is made more difficult by the roots, which can reach up to three meters deep. The plant must be dug up very generously in order to damage as few roots as possible. The above-ground parts of the plant, on the other hand, can be radically cut down - they have to, because otherwise you could not transport the monster. Sometimes a division by so-called root offshoots is also possible.

Propagation of cuttings in knotweed

The easiest way, however, is likely to be vegetative propagation via cuttings. The following procedure has proven its worth:

  • Take a herbaceous cutting about 10 to 15 centimeters long.
  • Use a sharp and clean knife for this.
  • The best time to do this is early summer, when the plant takes root more easily.
  • The interface should be as sloping as possible to make it easier for the plant to absorb water.
  • Remove all but the top two leaves.
  • Any flowers are also removed - they rob the cutting of the energy for root formation.
  • Mix two thirds of potting soil with one third of sand.
  • Dip the cut section in a rooting powder.
  • Plant the cutting about an inch deep.
  • Keep the substrate evenly moist.
  • Place a perforated plastic bag or mason jar over the cutting.
  • Ventilate several times a day.
  • Put the pot in a warm and bright place.
  • However, avoid direct sun.

tips

As soon as the cutting has formed roots, it forms new leaves and can then be planted straight away in its intended location.

Category:

Herbs