Layering (plant propagation)

“ Great numbers of plants which do not propagate naturally by means of layers are readily increased by this means under the direction of the grower. In most cases it is only necessary to lay down the branches, cover them with earth, and allow them to remain until roots are well formed, when they can be severed from the parent. Layering is one of the simplest methods of propagation, as the mother plants nurse the layer plants until they can sustain themselves. It is a ready means of multiplying hard-wooded plants which do not grow well from cuttings. ”

“ In some varieties which do not strike readily from cuttings, layering is considerably practiced by nurserymen. The Delaware is often grown in this way. Extra strong layers can be secured by layering in pots. A large « 196 » pot, filled with rich soil, is plunged beneath the layer. In this manner a layer may be rooted and separated even while carrying fruit. Layering in pots is employed only in special cases.
Green-layering is sometimes practiced upon new and scarce varieties, but strong plants are not obtained unless they are well handled by forceful culture after they are separated. ”

“ Layering is another garden operation dependent on the formation of these organs, and advantage is also sometimes taken of this tendency of some plants to produce roots when injured to reduce the dimensions of a plant when getting too large for the house in which it is growing. By gradually inducing the production of new roots from the central or upper portions of the stem, it becomes possible, after a time, to sever the connection between the original roots and the upper portion of the trunk, and thus secure a shortened plant. ”

“ Cutting into pieces only multiplies the pest; for each piece (Fig. 98) is already a plantlet, with its roots and with a bud in the axil of its scale-like leaf (either latent or apparent) , and with prepared nourishment enough to develop this bud into a leafy stem; and so a single plant is all the more speedily converted into a multitude. Whereas, when the subterranean parts are only roots, cutting away the stem completely destroys the plant, except in the rather rare cases where the root freely produces adventitious buds. ”

“ Here the branch emits roots, instead of the root emitting branches, as in the case of the sucker. Layering is frequently resorted to as a mode of propagation, it is very simple, easily performed, and, with some species, very certain in its results. Some plants will root readily if merely placed in contact with the ground, or very slightly covered with soil ”

“ Tap roots, grow vertically down into the soil. Tap root systems are less common in the tropical rainforest than in the temperate forest, partly because nutrients are concentrated in the surface layers of soil and partly because deep roots are also unnecessary as far as seeking for water is concerned. The physical work of anchoring the plant that is another function of deep taproots is often carried out by aerial or buttress roots to compensate. Lateral roots, which grow horizontally. Fibrous roots which form thick interwoven mats as in palm trees. Aerial roots, which grow in the air. ”

“ Many plants may be propagated by the process known as layering, which essentially consists in pegging down a shoot to the ground by means of a little crotchet stick, having notched with a sharp knife half way through a joint at the point where the shoot touches the soil, and covering the pegged down part of the shoot with a few inches of good gritty loam. ”

“ If we observe the strawberry plant, we find that at a certain season of the year it throws out offsets, and at certain distances a knob or knot arises, from which roots shoot into the earth, while from its upper centre a bud appears, and then a new plant is formed. The process of layering is to artificially produce this, and similar operations of nature. Some plants throw out roots whenever their stump or branches come in contact with the soil, but others require the assistance of art. ”

“ A slit is cut in the bark about where you would like to see roots growing. Then soil and florists' moss is bound about the wound. These may easily be kept moist. A paper pot could be put about the soil if one wished. The soil mass should be a ball of about six inches in diameter. When the new roots appear through the moss or poking out of the paper pot, cut the stem of the plant below the pot. ”

“ Large trees, generally, cannot be procured by layers, but only in those semiaquatic kinds which grow readily by slips. Whether it may be advantageous to fill up the vacancies of copse by layers, in preference to seed-plants, experience only can determine. The bark of trees or bushes raised by layers or cuttings is generally thicker than that of those raised from seed:—this might balance some deficiency of the growth in the case of oak-coppice. ”

“ Any part of the stem may produce them, but they most readily come from the nodes. As a general rule they naturally spring, or may be made to spring, from almost any young stem, when placed in favorable circumstances,—that is, when placed in the soil, or otherwise supplied with moisture and screened from the light. For the special tendency of the root is to avoid the light, seek moisture, and therefore to bury itself in the soil. Propagation by division, which is so common and so very important in cultivation, depends upon the proclivity of stems to strike root. ”

“ If no rain follows setting immediately, water the plants thoroughly—don't be satisfied with a mere sprinkling of the surface—and shade from the hot sun until the plants start to grow. One of the chief requisites in putting out a celery plant, and indeed almost any plant, is to press the soil FIRMLY ROUND, AGAINST, AND OVER THE ROOTS. This excludes the air, and the new rootlets form rapidly. Neither bury the heart nor leave any part of the root exposed. ”

“ It is during this rainy period that they make their growth and produce their flower spikes. Both the foliage and bulbs being small, they require careful attention as regards moisture at the roots.
We find the most suitable material in which to grow them, is a little fibrous peat and sphagnum moss with good drainage, so that the water may pass away without becoming stagnant. Some portion of this material should be changed each year, just as the plant begins to show signs of making its growth. ”

“ The lines of plants must run as far as practicable in geometrical regularity, particularly in sloping ground, never up and down or directly across the slope. If planted in the former manner, gutters or watercourses will form between the lines and the soil will be washed away, and if in the latter, the same injury will result between the shrubs. The lower side of each plant having its roots laid bare, the sun will act upon them, thereby causing the plants to shrivel up, languish and die. ”

“ In the first place, the enormous holdfast, ensured by the millions of points of adherence, enables the plant to withstand even powerful lever actions from above, and provides fixed points against which the root-tips can work as they drive deeper into the soil. In the second place, the intimate contact of the root-hairs and particles of soil, ensures that the films of water held by surface-action on the soil-particles and root-hairs shall be in continuity with the water saturating the cell-walls of the latter, and therefore with the protoplasm and cell-sap in their interior. ”

“ A small portion of air to be admitted on fine days, to purify the atmosphere of the house. Keep the surface of the soil in the pots free from weeds, as also from moss and lichen; but when doing so do not loosen the soil so as to injure the roots near the surface. Keep every plant free from dead leaves, and all climbing plants neatly tied up. The Achimenes, Clerodendrons, Erythrinas, Gloxinias, and the various bulbs will now be approaching a state of repose, and therefore will require but little or no water. ”

“ Of course, the more quickly the leaves throw off water, the faster the fresh supply pushes up the stem.
If the leaves do their work more quickly than the roots make good the loss, then the plant wilts.
When a leaf is broken from a plant, it soon fades. Its water supply being cut off, it has no way of making good the loss through the leaf mouths.
Just as the air in a balloon keeps its walls firm, so the water in the leaf cells keeps the cell walls firm. ”

“ Starting high above the ground, these grow at an angle from the stem and generally reach the soil. They serve the twofold purpose of supporting the stem and of supplying it with sufficient air. If, by accident, the underground roots die off, the plant relies entirely on these air and prop roots for support and food. The strong prop roots are generally of the same diameter throughout, though sometimes they thicken at the ends. Normally they never branch above the ground, but after reaching the soil very often divide. ”

“ In particular, a comparatively dry soil is desirable for grapes because of its influence on the development of the root system. In dry soils large root systems are developed in the search for the water that the plant must have. When intense droughts occur plants that have stood in damp soils have not sufficient roots to supply the necessary water to the aerial parts and the vines suffer in consequence. Some species and varieties are better fitted for withstanding an excess of moisture than others. ”

“ The subsoil should be also carefully examined by a boring augur, for a stiff moist clay, or marly bottom retentive of moisture, is particularly injurious to the plant. A dark, rusty-colored sand, or a ferruginous marl on a substratum of limestone, kills the tree in a few years. ”

“ Layering is a simple method by which plants may be multiplied. Moss Roses, nearly all kinds of hardy vines, like the Wistaria, Clematis, Honeysuckle, Ivy, and many others, are easily multiplied in this manner, together with most of our hardy shrubs. Many of our tenderer plants like Chrysanthemums, Verbenas, Heliotropes, etc., layer finely, by first bending the branches down to the ground, and partially covering them with sand or [Pg 26] soil. Pots may be plunged in the ground so that the limbs will not require to be bent much in layering them. ”

“ Plants that grow in the clefts of rocks should be planted in a sloping position, as water is then less liable to collect in the rosettes of leaves. Those that grow in cool, moist, spongy soil are best planted in a mixture of peat moss and earth. It is also important to notice whether the plant which is being cultivated was previously growing on limestone or granitic soil, for it is easy to add a little chalk to the earth if this is required. ”

“ When in flower the branches spread rigidly, but as the seed ripens the leaves begin to wither and drop off, the branches curl inward, and the plant becomes coiled up so as to resemble a small ball. In this state it is loosened from the soil and is drifted about with the sand over the arid plains. Should rain fall, or should it be blown into the water, the branches expand, the pods open, the seeds fall out, and it is a remarkable and newly-discovered fact that in the short space of twenty hours the seeds germinate and root. The plant will retain its susceptibility for years. ”

“ In general, those with masses of fibrous roots can be divided immediately after flowering. For upright and branching types, you can usually root stem cuttings in a frame or propagating box. If everything else fails, try layering. You can’t lose anything by it.
Seeds are planted the minute they are ripe, in a cold frame—or in flats that can be set in the cold frame—in a finely sifted mixture of equal parts of loam, woods leaf mold, and coarse sand. For varieties adapted to extremely acid soil, use half as much coarse sand as Michigan peat, without soil. ”

“ It should be understood, however, that in layering, the entire shoot is not to be covered; a good portion of the tip of the shoot should be in sight, and only the middle of the branch be under ground, and securely fastened down by means of a peg. All layering should be done while the wood is young; just ripe enough to bend without snapping off, and all hardy vines and shrubs are in condition to layer from the first to the middle of June. For tender plants any month during the summer will answer for the operation. Most tender plants will root in a month or six weeks. ”

“ These plants die every autumn. During the winter their decomposition produces a layer of leaf mould, in which a new vegetation of plants of the same species springs up again, and its rich growth mingling in its decay with that of the preceding year, the soil is thus annually raised by successive layers. ”

“ Make the holes intended for their reception round, capacious, and deep enough to hold their roots, without confining them in the least, and loosen the bottom well, putting new and fresh soil under their roots, breaking and pulverizing it during the operation, and frequently shaking the plant as you progress in filling up. When done, make all firm with the foot, leaving a circular cavity to hold the water they will require during dry weather. Give rods, and tie with bands all that need that support before they are left, lest they should be neglected. ”

“ Each rock should slant slightly inward and downward, to catch moisture and encourage it to run into the soil in the garden.
Provide plenty of soil for spreading roots, and a minimum depth of eighteen inches or more. Plants in shallow pockets may be stunted and will certainly dry out too fast during droughts. Whether or not you plant as you go depends partly on your agility. Don’t crush the first plants under your feet or knees as you set rocks and plants above them. It’s often faster and easier to spread out roots and make soil firm around them before the next rock is set in place. ”