Cuttings : There are various types of cuttings used for propagation of additional plants. The parts of a plant used to take cuttings, can be young, green stem-growths; semi-ripe wood; hard- wood; single leaves; buds; and roots.
Stem cuttings may be taken about 7-10cm in length of half-ripe shoots in July or August from such plants as cistus, hydrangeas and hebes. Some, such as those of camellias, may have a heel of the old wood attached ('heel' cuttings), though most cuttings are prepared by trimming them just below a node or joint ('nodal' cuttings) with a sharp knife or razor blade. Once you take the cuttings, they should be inserted in pots of moist sandy soil, or a mixture of peat and sand (75% peat:25% sand is optimum) or in a sandy propagating bed in a cold frame. Insert the cuttings to a depth of 2-4cm. Such cuttings should be shaded from the direct sunlight - white polythene is ideal - and be lightly sprayed over with tepid water each morning until roots have formed. Any cuttings that show signs of damping off (Stem rot) should be removed. In the spring young shoots may be taken from the base of chrysanthemums and dahlias which have been brought into early growth in a warm greenhouse or frame. These are known as soft stem cuttings and after they have been prepared by trimming them cleanly below a node or joint and removing the lower leaves, they should be inserted to a quarter of their depth in moist, sandy soil in a propagating frame with a temperature of about 55°F (13°C). Delphiniums, lupins, heleniums and many other plants, may be treated in this manner. Cuttings of the more tender plants such as dahlias may be rooted more quickly if the propagating frame is supplied with bottom heat and a very moist atmosphere is maintained, by inserting the cuttings in pots of moist sand or other rooting mixture, and plunging the pots in moist peat in the frame, and spraying them overhead each day. However, as far as the hardier plants, such as lupins and delphiniums are concerned, too much heat and too moist an atmosphere may easily result in the loss of cuttings through damping-off disease or other fungal diseases. When soft stem cuttings have rooted they should be potted singly, or in some instances they may be planted out in the open, provided they are not neglected. They should be protected from direct sunlight and drying winds while they are becoming established. Hard-wood cuttings, sometimes refer- red to as naked cuttings, are taken in October or November, of pieces of trees, shrubs, gooseberries, currants, hedging plants, such as privet and lonicera. Climbing roses may also be increased in this manner, but rooting is often poor. The cuttings are made from pieces of the current year's growth, about 20-30cm in length, pencil thick, with a clean cut made just below a bud eye. Remove all the leaves except a few at the top and insert the cuttings in sandy soil to a depth of about 10-12cm, making the soil firm around the cuttings. Prepared cuttings of hedging plants, gooseberries, currants and other really hardy plants, may be inserted in sandy soil in the open, choosing a reasonably sheltered place in partial shade—beside a hedge is often a suitable spot for a row of such cuttings. Cuttings of more choice shrubs should be placed in sandy soil in a cold frame, or have cloches placed over them. Most of these hardwood cuttings will have made roots by the following spring, when they can be planted out or potted up and grown on for a while before they are planted out in their permanent positions. Leaf cuttings: Healthy, well-developed leaves of numerous plants provide a useful means of propagation. Those that root particularly easily by this means include various begonias, such as Begonia rex, gloxinias, saintpaulias, streptocarpus, and some ferns, both tender and hardy. After removing a leaf from the parent plant make a few light incisions with a sharp knife across the veins on the underside and then lay the leaf on the surface of moist compost, consisting of peat and sharp sand. Peg the leaf down gently; hairpins are useful for this purpose. Leaf cuttings should be shaded from direct sunlight and have a reasonably warm and moist atmosphere. Begonia leaves, among others, will produce roots quite quickly, even when just placed in a saucer of water, but the difficulty is that the roots are so tender that potting on the young plantlets is quite a problem.Camellias are often increased by means of leaf-bud cuttings, which are similar, except that you take the leaf from the current year's growth, complete with a plump, dormant bud with a small piece of stem wood attached. Such leaves are inserted in sharp, moist sand in pots or in a propagating frame in March in gentle heat. Rooting cuttings in polythene film: An interesting way of rooting hard-wood or semi-hard-wood cuttings without inserting them in the normal rooting compost, is to use polythene film. The cuttings are prepared in the normal manner and a piece of film about 20cm wide and, say, 45cm long, is placed on the propagating bench. On one half of this, along the length, is placed a layer of damp sphagnum moss. The cuttings are then placed on this (their bases may first be dipped in hormone rooting powder if desired) about 2cm apart, their tops projecting over the edge of the polythene strip. The lower half of the strip of film is then folded up over the moss and the cuttings. Then, starting at one end and working towards the other, the strip of film with the moss and cuttings is rolled up tightly and tied top and bottom with raffia or twine. Roots should eventually form and these will be visible through the clear polythene. When most of the cuttings have rooted the roll can be untied and the cuttings potted up or planted out, taking care not to break the brittle young roots. The advantages of this method are that once the roll has been tied up no further watering is needed as moisture will not evaporate through the film (the roll should, however, he kept out of direct sunshine, on the greenhouse shelf or bench, or even on a window-sill), and that a number of cuttings can be rooted in a quite small space. Hygiene: Cuttings, particularly soft stem cuttings are liable to be attacked by soil-borne diseases or by virus diseases transmitted by insect vectors. Always use a clean razor blade or knife, if necessary sterilising the blade in a sterilant or disinfectant such as a weak solution of Jeyes Fluid. When a batch of cuttings of dahlias or chrysanthemums is being prepared for rooting it is essential to ensure that they do not flag while they are waiting to be inserted in the compost. As soon as each cutting has been taken from the chrysanthemum stool or dahlia tuber, drop it in a container of water to which a few drops of Jeyes Fluid has been added. Virus diseases may be transmitted by pests such as aphids. For this reason, when quantities of cuttings are to be rooted, it is advisable to fumigate the greenhouse beforehand and also to spray stools and tubers with a suitable insecticide and to dip cuttings in an insecticidal solution before they are rooted. Trouble with damping-off diseases can be prevented by watering John Innes cutting compost with Cheshunt Compound. This is less necessary with pure sand or sand/peat mixtures as both these should be reasonably sterile. Root cuttings: These consist of pieces of root about 5cm in length taken from plants with fleshy roots, such as anchusas, oriental poppies, Gypsophila, Verbascum, Romneya seakale and horse-radish. This is an autumn or winter job, the roots being lifted and then cut into pieces of the required length. The cuttings are usually made from roots which are about the thickness of a pencil, though where seakale and horse-radish are concerned they are made from side-roots and may be thicker than this. When making the cuttings make a clean, flat cut across the top and make the base wedge-shaped, then there will be no problem as to which way up the cuttings are to be placed when they are rooted in deep boxes of sandy soil. The top of the cuttings should only be just below the surface and the pieces of root can be placed side-by-side, horizontally or vertically (wedge-shaped end downwards), and made firm in the soil. The boxes should be stood in a cold frame or cold greenhouse for the winter months, and may be stood in the open in the spring. When top growth is evident, which is usually by the spring, the cuttings should be planted or potted up separately. With plants, such as herbaceous phlox. Primula denticulata, or the little alpine Morisia monantha, which have much thinner, thread-like roots, these may be treated in the same manner except they are merely placed onto the soil, in boxes or pots, and then lightly covered with sandy soil. Pipings: The rooting of pipings is a method of propagation used primarily for members of the dianthus family, particularly carnations and pinks. Pipings are in effect a type of cutting, but instead of using a knife to make the cutting, the shoot is pulled out from the main stem. The tip of the leading shoot is held gently between the thumb and forefinger, just above the first node, and pulled until it slides out of the node where the first pair of leaves has formed. The main part of the stem should be held with the other hand. There is no need to prepare it in any further way, and the piping can be inserted in a sandy compost to root in the usual way. Pipings are usually taken in early summer from young non-flowering shoots. Vine 'eyes': Pieces of dormant one-year vine rod, each with a plump bud, are cut into lengths of about 30cm, which are virtually stem cuttings. With the aid of a sharp knife remove a strip of wood 2mm thick from the wood behind the bud to encourage root formation. The pieces of rod are then pegged down individually into pots containing sandy soil and placed in a propagating frame with a bottom heat of 24°C.
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