Learn all there is to know about layering outside plants and houseplants.
By David Squire
Propagation (Fox Chapel, 2016), by David Squire, is the essential guide to raising new plants for the home and garden for both novice and experienced gardeners. Squire contributes his lifetime experience with cultivated and native plants with an interest in historical medicinal roles, folklore, and customs of plants. This excerpt is from “Division and Layering” section.
This is both an easy and an assured way to increase shrubs, trees and vines. However, it is not quick and may take up to a year before the layer develops roots and can be severed from the parent plant. It is then planted either into a nursery bed or directly into a border. For shrubs and trees to be layered, it is essential that a relatively young shoot is low enough to be lowered to the soil, and sufficiently pliable to be bent into position with its tip upright.
Layering is an excellent way for home gardeners to increase shrubs and vines, but the area where the stem is layered must be left undisturbed for up to a year. Therefore, before starting to layer a plant, remove all weeds from the area, especially perennial types that will regularly produce new shoots unless their roots are dug up.
Select a healthy, low-growing, vigorous shoot that is up to two years old. Form a shallow trench that slopes to 3 – 6 in (7.5 – 15 cm) deep at its lowest point, 9 – 18 in (23 – 45 cm) from the shoot’s tip. Lower the shoot into the depression and bend its tip upright. Wound the stem, either by making a tongued cut at the point of the bend or by cutting halfway around the stem and removing the bark.
Use a piece of bent wire or a wooden peg to hold the stem in the ground. Firm soil over the stem, so that its surface is level. Insert a bamboo cane and tie the shoot to it, to hold it secure and upright.
When new growth appears on the layered shoot, remove the soil, sever the shoot from the parent and plant into a nursery bed or directly into a border.
Twenty Shrubs, Trees and Vines that can be Layered• Amelanchier (June Berry/Snowy Mespilus)
This is a popular and easy way to increase plants with long, pendulous stems that can have their tips lowered to the ground and buried in soil. Popular plants that can be tip-layered include Blackberries, Loganberries and other Hybrid Berries.
During late summer or early autumn, select a long, young, healthy stem and lower it to the ground. Use a trowel to form a hole, 3 – 6 in (7.5 – 15 cm) deep, where the tip touches the ground. Alternatively, to make transplanting easier when roots have formed, bury the tip in a 6 in (15 cm) wide pot that is itself sunk to its rim in the soil to help keep the compost moist and cool.
Position the tip in the hole and use a piece of bent wire to hold it in position. Cover the tip with soil and level and firm the surface. Then, water the area, keeping it moist until rooting is complete. Rooting takes a few months; in spring (sometimes earlier) sever the stem about 1 ft (30 cm) from the tip. The rooted tip can then be transplanted to a nursery bed or, preferably, its final growing position.
Layering is an easy and assured way to increase houseplants. However, it is not fast; it often takes several weeks for new roots to form, when the rooted parts can be severed from the parent plant and transferred to individual pots. It is well suited to increasing houseplants with long and flexible stems (see below for a range of suitable plants) and it has the advantage of a high success rate. It is also a technique that inevitably captures the attention of children.
Late spring and early summer are the best times to layer houseplants, when they are starting to grow strongly after, perhaps, a partially dormant period during winter. This subsequently allows plenty of time for the layered stems to develop roots, and for you to sever and transfer them to pots before the arrival of the less vigorous growing days of autumn. Always check that the parent plant and the shoots being layered are healthy and free from pests and diseases.
Select a healthy shoot and bend it sharply, without severing it, 4 – 6 in (10 – 15 cm) from its tip.
Press the bend into a pot of potting soil and secure it in place with a bent wire; firm the soil, and water.
Keep the soil moist and, when roots have formed, use sharp scissors to sever the stem close to the new plant.
Lower a stem into a pot of soil and press it into the surface; secure it with bent wire.
Firm the soil around the young shoot; water the soil to settle it around the shoot.
When young shoots appear from the layer’s tip, use sharp scissors to sever it from the parent.
Houseplants for Layering• Cissus antarctica (Kangaroo Vine)
When several stems are layered at the same time from a parent plant, place all the pots in a large plastic tray. This makes it easier to move the parent plant and, perhaps, three or more small pots at once without disturbing the layered shoots.
Reprinted with permission from Propagation, by David Squire and published by Fox Chapel, 2016.