How do I layer a shrub to make a new plant?

Layering succeeds where cuttings fail because it removes the problem cuttings have. A cutting has to survive with no roots and no water supply; a layer stays plumbed into its parent throughout. The cost is time — a year rather than six weeks — and that you can only make as many plants as you have low branches.

What you'll need

• A low, flexible, one or two year old branch
• Bent wire pegs, tent pegs or a large stone
• A short cane and soft tie
• Compost and grit to improve the soil
• A sharp knife (optional)

Step by step

1. Pick the right branch.Young, flexible, growing near the ground on the outside of the plant, long enough that 200 to 300mm of tip remains beyond the point you will bury. Old stiff wood snaps and roots badly.
2. Choose the timing.Spring or early autumn are both good. Autumn layers spend the winter making callus and root in spring; spring layers get a full season. Either way, expect about twelve months.
3. Prepare the ground where it will touch.Scoop out a shallow depression about 100mm deep and work compost and grit into the base. Rooting into unimproved hard ground is much slower.
4. Strip the leaves from the section to be buried.Leaves underground rot and take the stem with them. Leave the tip and the growth beyond the buried section intact.
5. Wound the underside at a node.A shallow angled cut into the bark on the underside, or a firm half-twist of the stem. It interrupts the flow of sugars back to the parent so they accumulate at the wound, which is what triggers rooting. Do not cut more than a third of the way through.
6. Peg it down firmly.A bent wire staple, a tent peg or a heavy stone over the wounded section. It must not move — movement breaks the fine roots as they form.
7. Bury it and firm the soil.Cover with about 100mm of the improved soil and firm it down with your foot. Good contact between stem and soil is what matters.
8. Tie the tip upright.A short cane and a soft tie so the growing tip is vertical from the start. It becomes the main stem of the new plant, and a tip left lying flat produces a sprawling shape.
9. Keep the spot damp through the first summer.The buried section will not root in bone-dry soil. It is the one bit of maintenance the method needs, and a stone or a mulch over the spot mostly handles it.
10. Check after about twelve months.Scrape the soil back carefully. A decent mass of new roots means it is ready; a few thin ones mean give it another season.
11. Sever in stages, then lift.Cut the branch on the parent side of the roots and leave the new plant in place for another four to six weeks so it adjusts to standing alone. Then lift it in autumn or early spring and plant it where you want it.
12. Use tip layering or mound layering where it suits.Blackberries and hybrid berries root from the tip pushed into the ground. Old, congested shrubs can be mounded with soil over the base in spring so each stem roots and can be detached in autumn.

Tips

• Many shrubs layer themselves where a branch rests on the ground. It is worth looking underneath before doing anything — you may already have a rooted plant.
• Peg down two or three at once. It costs nothing and the failures do not matter.
• This is the reliable method for the plants that are notoriously hard from cuttings — magnolia, rhododendron, camellia, hazel, viburnum and many climbers.

Common mistakes

• Cutting too deeply when wounding — More than about a third through and the branch snaps or dies. It is a nick, not a cut.
• Not pegging it firmly — Any movement in wind snaps off the fine roots as they form, and the layer simply never takes.
• Severing as soon as roots appear — The new plant has a small root system and a full canopy. Sever, then leave it in place for a month or more before lifting.
• Letting the spot dry out in summer — Rooting stops in dry soil. Water it as you would a newly planted shrub through the first season.

If it doesn't work

Questions people ask