A Detailed Guide to Three Methods of Layering Propagation for Flowers

Layering propagation of flowers means nicking a section of a parent plant's branch and burying it in soil; once roots form, it is cut away from the parent plant to become an independent new plant. It is generally divided into three types: simple layering, mound layering, and air layering.

1. Simple layering. It is mostly used for vine flowers with soft and slender branches, such as winter jasmine, Japanese honeysuckle, and Chinese trumpet creeper. When layering, bend the outer branch of the parent plant into an arc, nick the protruding part of the downward bend, bury it in soil, then use a hook to secure the downward-bent part; once it has rooted, it can be cut away from the parent plant and transplanted separately.

2. Mound layering. It is suitable for deciduous shrubs with strong clumping growth and relatively hard, inflexible branches, such as red osier dogwood, dwarf flowering almond, and yellow rose. In early summer, perform ring-barking of about 1 cm at about 25 cm above the ground on the lower part of the branches, then mound soil around the parent plant, burying the lower half of the entire clump in soil, and keep the soil mound moist. After it has rooted sufficiently, before budding in early spring of the following year, dig open the soil mound, cut the branches away from the parent plant at the base, and divide and transplant them.

3. Air layering. It is used for evergreen flowering trees and shrubs whose branches are difficult to root and not easy to bend, such as Michelia alba, Aglaia odorata, and Michelia figo. It is generally carried out during the peak growing season. Select well-developed 2-year-old branches, perform ring-barking at an appropriate position, then use a plastic bag filled with peat soil, mountain soil, moss, etc., to wrap the branch, water thoroughly, tie and secure the bag opening, and thereafter supply water in time to keep the growing medium moist. After the branch has rooted, cut it away from the parent plant from below the bag, remove the wrapping, plant it with the soil into a pot, place it in a shady place for care, and only expose it to full light after a large number of new shoots have sprouted.

For some flowers that are relatively soft and easy to separate from the bark, when using the air layering method, in addition to ring-barking at the air layering site, twig twisting can also be used, that is, twisting the layered part with both hands so that the phloem and xylem at the air layering site separate; applying some growth hormone to the wound can promote rooting.