LETTER XII.

OPERATIONS OF GARDENING.--DIGGING, FORKING, AND HOEING.--SOWING SEEDS.--TAKING OFF SUCKERS.--MAKING LAYERS AND CUTTINGS.--BUDDING, GRAFTING, AND INARCHING.--PRUNING AND TRAINING.--DISBUDDING.--MANURING.--KEEPING FRUIT IN A FRUIT-ROOM.

Digging is the first operation necessary in gardening, as nothing can be done in the way of cultivating the soil till it has been first pulverised, so as to allow the fine delicate roots of the plants to penetrate among its particles. It is also necessary that the air should have access to the roots of plants, as they depend for their nourishment almost as much on the carbon and other elements which they absorb from the air, as on those which they obtain from the soil. On this account it is necessary, not only to dig the soil well before any thing is planted in it, but also to fork it over occasionally whenever its surface becomes hardened and impervious to the air and rain. When manure is applied also, it is customary to dig it into the soil; and ground is occasionally trenched in order to bring up fresh soil to the surface, whenever the surface soil appears to be exhausted and to want renewing. The operation of digging requires considerable strength, as it requires first to be able to force the spade into the ground, and then to raise as much earth as will lie upon the blade and turn it over. It is, however, a fine healthy occupation, not only from its calling the muscles into vigorous action, but from the smell of the new earth being particularly invigorating; and you might have a lady's spade, with a smooth willow handle, that will enable you to dig a small bed without much difficulty. You will be surprised, however, to find, if you try the experiment, that there is an art in digging as well as in every thing else; and that it is extremely difficult, both to dig in a straight line, and to make the ground look even tolerably level after it has been dug over. _Raking_, though it appears so simple, also requires considerable skill to make the ground look smooth and perfectly level. _Forking_ is not so difficult, as it merely requires to have the fork pressed into the ground, and then pulled backwards and forwards, so as to loosen a portion of the soil without turning it over.

There are two sorts of _hoes_: the _draw-hoe_, which is used for drawing up the earth to any plant that is to be earthed up; and the _thrust-hoe_, which is principally used for destroying weeds. There are many varieties of both these forms, but the common kinds, I think, you will find the best. The most useful instrument, however, for you will be a _trowel_, and this you will find indispensable, as, without it, you will not be able either to transplant or pot a single plant. Some persons use what is called a _transplanter_, to enable them when they take up a plant, to remove it without disturbing the roots; but, as far as my own experience goes, I think these instruments are more troublesome than advantageous, and I prefer using a trowel. You will also want a _budding-knife_, and a sharp knife for making cuttings; and you will find a pair of _pruning-shears_ with a sliding-joint extremely useful for cutting off dead wood, or removing any badly-placed branches.

Plants are propagated either by seed, or by division. When they are to be propagated by _seeds_, the ground must be either dug or forked over and made level. It is then firmed by beating it with the flat part of the spade, rolling it, or in any other manner; and the seeds are scattered over it, if they are to be sown broad-cast, and covered with earth the same thickness as themselves. When seeds are to be sown in drills, a narrow furrow must be made, by drawing a stick along the ground in a straight line, or in any other way so as to make the bottom of the furrow firm, and the seeds must be dropped into it at regular distances. The furrow is then filled in, so that the seeds may be covered to the same depth as their own thickness; and the earth is slightly pressed down, and afterwards raked over. Larger seeds are sown in separate holes made by a dibber, as are the sets of potatoes; but the after processes are the same in all. Bulbs and tubers are also planted in the same manner; taking care that the eyes of the tubers are uppermost, and the flat part of the bulbs downwards. In planting Ranunculus tubers the claws should be downwards, and if any are broken they should be cut off smooth with a sharp knife.

There are several ways of propagating plants by division, viz. taking off suckers, making layers and cuttings, and budding, grafting, and inarching.

Propagation by _suckers_ is very simple. Many plants have a portion of their stems under ground, from the buds in which new upright stems rise into the air and fibrous roots descend into the ground. It is thus only necessary to divide the horizontal underground stem by the spade, or by opening the ground till the stem is found, and then cutting it through with a knife, and to take up the young plant which has sprung from it carefully and without injuring its roots, cutting off the remains of the old plant before the new one is replanted. Suckers sometimes spring from the collar of the old plant, and when this is the case they require more care in removing them, to avoid injuring the plant from which they spring.

_Runners_ are suckers proceeding from horizontal stems above ground, and _offsets_ are the suckers of bulbs, as they proceed either from the root-plate, which is the compressed stem of the hyacinth, or from the main body of the corm, which is, in fact, the stem, as in the crocus.

_Layers_ are produced by imitating the process of nature in making suckers; as, in making layers, a joint of the upper stem is buried in the ground, and kept moist to induce it to throw out roots; the buried stem being generally slit or twisted at the joint, so as to prevent the return of the sap, and to occasion it to expend itself in roots instead of circulating in its ordinary way through the branch. As soon as a layer has produced roots it becomes the same as a sucker, and may be treated in exactly the same manner.

_Cuttings_ are portions of a plant cut off just below a bud, and buried in the earth to induce them to throw out roots; which is done most effectually by exposing them to warmth and moisture, and shading them from the light, as that has a tendency to draw the sap towards the leaves, whilst warmth and bottom heat dispose the cuttings to throw out roots. On this account cuttings always strike most readily when the pots, in which they are planted, are plunged into a hotbed, and covered closely with a hand-glass. It must be observed in making cuttings, that they ought in most cases to consist of two buds; from the lower one of which the new roots are to spring, while the upper one is to produce the stem of the new plant. Cuttings must always be made quite firm at the base; and they generally strike most readily when the bottom of the cutting, which is cut through a joint and quite flat, rests against a piece of the drainage, or even the bottom of the pot, being in both cases pressed so closely against its earthenware support as to exclude the air. When a cutting is made, most of the leaves are removed, as the evaporation from them is greater than the plant can support while it is without roots. Cuttings of succulent plants are generally laid upon a shelf to dry before they are put into the ground, as if this is not done the wounded part is apt to become rotten, and to decay. Cuttings are generally struck either in sand or very light earth, in order that the young roots may meet with as little obstruction as possible.

_Pipings_ are portions of pinks and carnations pulled asunder at a joint instead of being divided with a knife, and afterwards planted, and treated exactly like cuttings.

_Budding_ is taking off a single bud or eye, called a scion, from one plant, and inserting it in another plant called the stock. This operation is generally performed in July or August. In the first place, a slit is made on each side and above and below a leaf which has a healthy bud in its axil, that is, just between the foot-stalk of the leaf and the branch on which it grows. The bark of the branch containing the bud and the leaf is then detached from the branch, by passing under it the bone handle of the budding-knife, which is made flat and thin on purpose, and raising it gradually up. If the bark has been raised carefully and properly, there will generally be a little bit of wood just under the bud, which must be carefully taken out, so that not the smallest particle of wood is left on the under side of the bark. A long slit is then made in the bark of the stock, with a cross slit at the top, and, the bark being gently raised at each of the corners made by the intersection of the long slit and the horizontal slit, the piece of bark with the bud attached is carefully introduced under the bark of the stock, which is closed over it, and bound tightly with a bit of bast mat, in order that the bark containing the new bud may be pressed as closely to the wood of the stock as possible. If the operation has been properly performed and the bud was a healthy one, it will soon begin to swell; and, when it does so, it will push off the foot-stalk of the old leaf that was taken off with it, so that when this foot-stalk falls it is a sign the bud has taken. When the bud has developed itself into leaves, the ligature should be loosened to allow the branch of the stalk to expand. The operation of budding requires a good deal of nicety: first, to avoid wounding the wood of the stock in slitting the bark; and, secondly, to make the bark of the scion fit quite closely to the wood of the stock, as, if the least vacuity is left between them, the bud will wither instead of beginning to grow.

_Grafting_ differs from budding, in the scion consisting of several buds instead of one. It is also performed at a different time of the year; as March and April are the proper seasons for grafting, whereas budding is never performed till after Midsummer. In grafting, sometimes the head of the stock is cut off, and sometimes only the branch, and the scion is selected according to the size of the part to which it is to be attached. When the scion and the stock have been both chosen, they are cut slantingly, so that one may fit into the other; and care being taken that the bark and soft wood of the two unite, at least on one side, the two pieces are bound together, and the ligature is covered with what is called grafting clay, that is, a mixture of stiff clay, with a fourth part of fresh horse-dung, and a small quantity of cut hay. Another kind of grafting clay is composed of equal parts of stiff clay and cow-dung. It is of very little consequence whether the scion and the stock are of the same diameter, provided they are so cut and fitted, as to leave no vacuity between them, in those parts where the union is to be effected; and, to keep them quite closely attached to each other, it is customary to form a tongue, or little projecting part, by making a slanting cut in the scion, and to make a corresponding slit in the stock to receive it. There are several kinds of grafting; but that which I have described, and which is called whip or tongue grafting, is the most common, and it is always performed with the firm or ripened wood. There is, however, another kind of grafting, now becoming common in the nurseries, which is performed with the young, or unripened wood, and this is called _herbaceous grafting_, because the parts of the stem with which it is performed are as succulent as the stems of herbaceous plants. In this kind of grafting, the shoot of the stock is broken off about two inches below the point, and all the leaves are taken off except two, one on each side, which are left to draw up the sap. The stock is then split with a very sharp knife between the leaves left on it; and, the base of the scion having been cut into a wedge-shape, it is fixed into the cleft made in the stock, which is bound tightly up with strips of cerecloth, or coarse cotton cloth covered with grafting wax, made of equal parts of turpentine, bees' wax and rosin, with a little tallow, melted together. Sometimes plants, especially camellias in pots, are grafted in this manner, and placed in a hothouse under hand-glasses, and the pot surrounded with moss, to keep the cutting as close as possible. This mode of grafting is of French origin, and it is called _la greffe etouffée_.

_Inarching_ bears considerable resemblance to layering, as it is performed without separating the part which is to form the new plant. A branch is bent from a living plant, and partly cut through, and, the tongue thus formed being introduced into a slit made in another plant, the two are bound closely together. It is obvious that this mode of grafting, which is called inarching, can only be practised with plants in pots, as it requires the two plants that are to be united to be brought close together, and to remain so till the graft has taken effect.

You must observe that, in all kinds of grafting and budding, there must be a considerable degree of resemblance between the scion and the stock, for the graft to take effect. Thus, though one stoned fruit may be grafted on another, such as the almond or peach on the plum, a stoned fruit cannot be grafted on a kerneled fruit, such as a plum on an apple or a pear. In the like manner, an apple cannot be grafted on an orange, which was formerly supposed to be done, to produce a pomegranate; nor a rose on a black currant, which it was formerly believed would produce a black rose. It is true that plants are sometimes sold in Italy which appear to have been unnaturally grafted, such as a rose upon an orange; but it will be found, when closely examined, that the pith of the orange has been artfully scooped out, and the stem of the rose tree introduced into the hollow space thus formed, through a hole made in the stem close to the root. In this way the two plants may appear to be one for some time; as the stem of the orange tree will live and produce leaves two or three years after the pith is removed, provided the operation has been performed carefully.

The other operations of gardening are _pruning_ and _training_, and, as I have already spoken of these when treating of the different trees, I have only to add here that the great art in pruning is to give a clean sloping cut without bruising the bark, as nature will make an effort to cover the wound if the edges of the bark are left in a healthy state. The use of a sloping cut is, to prevent the water from lodging on a wounded part. Trees should never be cut in a hard frost; and as little as possible in summer, as every branch taken off while the plant is in a growing state excites it to make fresh efforts to throw out new shoots. Many persons look over their trees in summer, and rub off all the buds which they think likely to produce useless shoots; and this practice, which is called disbudding, is a very good one, as it prevents the tree from wasting its strength unnecessarily. The principal object to be attained in training a fruit tree is, to make the plant produce as much fruit as possible; and for this purpose the branches are bent backwards and forwards to cause obstructions in the sap, as it is only from places where there is an accumulation of sap that flowers and fruit are produced. Another object in training standard trees is to let the air into the centre of the tree, so that it may ripen the wood; and a secondary object in training trees against a wall is, that every part of the wall may be covered.

I cannot quit the subject of gardening without saying a few words on _manures_. The object of manuring ground is, to supply the soil with certain properties which are necessary for the nutrition of the plants, and this is done partly by mixing with it some kind of animal or of vegetable manure, and partly by adding some earth, in which the soil of the garden may be deficient. The new manures which have lately been so fashionable are of both kinds: guano is the dung of sea birds, which has been accumulating for ages on islands off the western coasts of Africa and South America; and nitrate of soda and Humphrey's compound are mineral substances which are very efficacious in promoting vegetation. The best vegetable manure is formed from decayed leaves, and this is a manure which may always be used with perfect safety; whereas the others are very injurious if used in too huge a quantity.

No kind of animal manure should be used in a garden (except for making hotbeds) till it is thoroughly decayed and all fermentation is gone off; as while it is in process of decay the gases it evolves are decidedly hurtful to plants. Those manures which abound in nitrogen, such as stable manure and the dung of birds, are the strongest and most dangerous; as if used incautiously they will blacken and shrivel up the leaves of the plants to which they are applied. Guano and pigeon's dung are very much alike in their properties, and both are of an extremely caustic nature; so that they should only be used in very small quantities, or be very much diluted. One ounce of guano to a gallon of water is a common proportion; or the guano may be mixed with six or seven times its own bulk of loam, peat, or charcoal, and dug into the ground before the crops are sown: if applied afterwards as a top dressing, it should be either in wet weather, or the soil should be well watered. Charcoal is very efficacious in some cases, but it appears variable in its action; as sometimes it produces scarcely any effect. Nitrate of soda and saltpetre act principally by supplying a particular kind of earth to plants that are in want of it, and of course will not suit all plants; but they are also of service in keeping the earth moist, and this, when not carried to an excess, is always useful.

When it is wished to keep plants constantly in a growing state, the soil should be rendered rich, and the plants should also be watered frequently, so as never to suffer the soil to become quite dry; equal care being taken to keep it free from stagnant water, which would rot the roots. When, however, the plant is to be hardened, to stay out the winter, it should be kept as dry as possible, and no manure should be applied for some time previously to the cold weather setting in. Nothing is less generally understood than the use of manures. They are in fact food; and should not be given to plants in excess, any more than children should be crammed with food. Starving and repletion should both be carefully avoided; and the great art of the cultivator is shown in supplying plants with food only when they need it. Too much water will sometimes produce leaves and stems instead of fruit and flowers; and shoots of great luxuriance very frequently do not ripen, and are killed by the first frost.

After telling you how to grow fruit, I must next tell you how to keep it. A proper _fruit-room_ should be fitted up with broad shelves, or wooden trays with rims in front to prevent the fruit from falling off, and divided into compartments for the different kinds. There is generally a large table in the centre for sorting the fruits, and a thermometer should be hung on one side to regulate the temperature. According to Dr. Lindley, the essential points for a fruit-room are, "a low and steady temperature; dryness to a certain point, for apples are found to keep best in a rather damp atmosphere; and exclusion of the external air:" to this he adds, that it is necessary to keep the fruit in comparative darkness, to prevent it from becoming shriveled and ripe prematurely; that the temperature of the room should not be much above 40°; and that the shelves should be of white deal, as that wood does not give an unpleasant taste to the fruit.

Fruits keep best when laid separately, so as not to touch each other; and sometimes pears may be kept by packing them in fern, and grapes by packing them in jars in sawdust. Walnuts and chestnuts should be kept in rather a moist place, and covered with fern to exclude the air as much as possible, as they are much injured if they are kept too dry.

I may here mention that when sweet chestnuts are sent to the table, they ought always to be boiled first, and roasted afterwards; as, if roasted without previously boiling, it is scarcely possible to cook them sufficiently to make them wholesome, without burning them. After they have been boiled, before they are put down to roast, care must be taken to prick the skins; as, if this is neglected, the chestnuts will fly about in all directions as soon as the outer skin becomes parched.