Growing trees and shrubs from cuttings
Most species may be grown from seed, but we have mentioned some which propagate easily from cuttings or by layering shoots: these are forms of vegetative reproduction. Unlike sexual reproduction from seeds, which is the union of pollen (male) and ovule (female), vegetative reproduction allows no genetic mixing or diversity. All the young plants are genetically identical to the parent.
Cuttings are often used for garden species which may not be fertile, for example plants which do not grow naturally in our climate, or when it is important that all plants should be exactly the same.
For some of our native species, it is the easiest way to propagate large numbers and is especially used for willows. To take cuttings first cut a young branch, one or two years’ growth, from your parent tree or bush. This is generally done in autumn or winter.
A strong sharp pair of pruners is essential for good quality cuttings. In a nursery set-up this task is carried out indoors on wet days when other work would be awkward. A branch or shoot of willow can be up to 2.5 metres long in one or two years and therefore ten or so cuttings from each one is possible. Each branch is removed by executing a straight cut, just below a bud, at its base.
Next any old leaf growth or side branches are cleared neatly from the shoot. Growth thinner than pencil thickness at the top of the branch is removed, being too thin to be suitable. Cuttings can be from 15 – 24 cms long, making sure each one has at least three buds on it.
Proceeding from the base of the branch upwards a straight cut is made just under a bud; then six or nine inches up a slanted cut is made just above bud. Following each top cut short piece of waste wood is removed when moving up to the next base cut. The slanted cut at the top serves a few purposes among which are:
- Making it obvious which is the bottom end when planting prevents water lying on top of the cutting which can cause rot.
- Prevents water lying on top of the cutting which can cause rot.
The ‘pegs’ can be planted straight away. The flat base end is pushed into the soil to half or two thirds the depth of the ‘peg’. Mulching is easy with cuttings as it can be carried out before planting if required (see later section on Care of Young Trees). Cuttings can be ‘heeled in’ as a storage method if required: damp coarse sand is ideal for this.
Note: The use of one pointed end and one flat surface is generally accepted, but some nursery men use them the other way round – the pointed end is pushed into the soil so you are pressing on the flat end, which is pushed in at an angle so that it will shed rain.
It doesn’t matter which way you choose to do it, so long as you get the cutting the right way up, i.e. with buds ready to grow upwards!
