Q.Is There Such A Thing As A Dwarf Leycesteria (Himalayan Honeysuckle)?
I understand that Leycesteria is normally a shrub which grows up to 20 feet tall. However, my neighbour (with whom I am not acquainted) has one, growing in full sun, which never reaches more than 3 feet, looks healthy, is very floriferous and never shows any signs of having been pruned. I can find no reference to a dwarf Leycesteria on any horticultural website. Could it be genetic or environmental factors which are responsible for its small stature? And if my neighbour allows me to take a cutting, when and how should I do this?

Certified GKH Gardening Expert
Under ideal conditions, this plant doesn't usually exceed 6 feet, with some of the shorter cultivars being around 3 feet tall. There are a few that will get taller and some that remain slightly shorter, however.
Here are some articles that will help you to take cuttings and care for the plant:
https://www.gardeningknowhow.com/garden-how-to/projects/rooting-plant-cuttings.htm
https://www.gardeningknowhow.com/garden-how-to/propagation/cuttings/root-stimulating-hormone.htm
https://www.gardeningknowhow.com/garden-how-to/propagation/cuttings/honey-root-hormone.htm
https://www.gardeningknowhow.com/ornamental/vines/honeysuckle/himalayan-honeysuckle-plants.htm