Plant Propagation – Layering
Plant Propagation by the Layering Method
It is well worth experimenting with layering as a method of propagation, especially for plants that are expensive to buy or difficult to find, and those that you have found hard to root from . Layering happens naturally with some plants, such as and , when the stems that come in contact with the soil form their own roots, while attached to the parent plant.
Border carnations are usually propagated by this method. In high summer, when they have just finished flowering, choose a healthy, non-flowering shoot. Without removing it from the parent plant, strip off its lower pairs of leaves, leaving a tuft of foliage at the end of the shoot. Using a sharp knife, make a thin slicing cut 2.5cm (1in) or so long, from the bump in the stem where the last pair of leaves were removed up to just below the remaining tuft of leaves. This should result in a slender tongue of stem that opens away from the parent plant. Work some horticultural sand into a small hole in the appropriate position and lower the shoot down into it, with the cut kept open. (By encouraging the shoot tip into a vertical position, the cut should open.) Peg it firmly in with a U-shaped piece of bent wire, leaving the tuft of leaves exposed above the soil surface. Top up with the mixture, and water thoroughly. In about two months the layered shoot should have rooted.
Magnolia,, Rhododendron and choice members of the Ericaceae such as Kalmia and Menziesia may also be propagated this way. Choose a vigorous shoot near ground level and pull it gently towards the soil. Work out where the middle of the buried portion is going to come and then wound the bark at that part, by removing with a sharp knife a thin piece of bark about 2.5cm (1in) long. Make a small hole about 10cm (4in) deep and work some horticultural sand into the soil at the bottom of the hole. Peg the shoot firmly into the sandy mixture with a U-shaped piece of bent wire, and fill up the hole with the sand and soil mixture. It may be necessary to stake the shoot tip, to keep it vertical. (Do not use a multi-purpose compost for layering these plants, since it may contain lime.)
Layering is also a useful way of propagating heathers. In spring, bend down some of the outer stems of the plant into the soil, so only the tips of the shoots are showing, and hold them down with a stone or piece of bent wire. The following spring the young plants may be separated from the parent and transplanted. Daphne cneorum, a lovely prostrate plant, with fragrant rose-pink flowers, is another ideal subject for layering. Simply mound up the stems of the plant with horticultural sand, working it down between the branches in spring. By early autumn some of the stems will have taken root and may be potted up or planted elsewhere.