HOW to prepare and apply manures is a matter in which every cultivator of the soil must feel deeply interested. It matters not to what expense and trouble we go to procure the finest fruits or vegetables, and the most beautiful trees, shrubs, and flowers; or with what excellent taste we may arrange our parterre; unless we furnish the soil with such quantities and kinds of fertilizing materials as will ensure a vigorous, luxuriant, and healthy growth. The agriculturist may stock his farm with the purest and best blood of animals that the world can produce, or he may plant the best improved grains and grasses or root crops that money will purchase; but without judicious and liberal feeding in the one case, and skillful, thorough culture in the other, he will be no better off in the end than his neighbor, who has remained satisfied with such stock and such seeds as he could most easily and most cheaply procure. This every one will cheerfully admit in theory, but a great many deny it in their practice; and thus the obstinate opposers of improvement and progress have been furnished with their strongest arguments.

Here, they say, are Mr. Brown and Squire Jones, who have spent fortunes in collecting new and fine things from all parts of the world - they have every known variety of fruit and flowers - they have employed celebrated gardeners to lay out their grounds, and have spent thousands upon labor; and what have they ? Why, they have to come over here to us and purchase a supply of fruit for their families; and the old lady across the way, whose garden is a mere patch, and who does all her own work, can show more and finer flowers than they can any day in the year! This is not an imaginary case; we have repeatedly heard these remarks, and had occasion to regret the pernicious influence of such examples. On the other hand, we could point to instances where a single example of a small garden successfully cultivated, has awakened an entire village and neighborhood, and set them at planting and gardening with the greatest enthusiasm - and upon the right principle.

One of the very first matters that should occupy the attention of persons embarking in horticulture, whether on a large or small scale, should be the preparation of his soil. This ought to be the starting point; and there is probably no other item in the entire routine of culture in regard to which beginners find themselves so puzzled, or so completely in the dark. If every crop and every soil could with propriety be furnished with the same quantity and kind of manures or fertilizers, it would be a simple matter; but such is far from being the fact. What may be fit and proper for one soil and one sort of crop, may be utterly ruinous to others; and therefore a great degree of judgment and discrimination becomes necessary. Much may be gathered from the instruction of books and the experience of others; but local circumstances, apparently trivial, exert such a weighty influence that nothing save actual experience with our own soils can afford an unerring and perfectly reliable guide. This we have found true in our own practice.

We have no hope, therefore, in being able to write anything that every man may carry out to advantage, and will merely aim at directing attention to certain well established facts and principles that may aid in putting the inexperienced on the proper course.

One great error, and, as we believe, a very prevalent one, is that of applying the same kind of manure to the same soil for a great number of years in succession. We will take, for instance, town and village gardens, and see how the case is with them. A cow and a horse, and perhaps a pig, are kept on the premises, and whatever manure they may produce, or such a quantity of it as may be considered necessary, is annually applied to the garden without any admixture of other material, and, in most cases, without being very properly prepared beforehand. At the same time, the ground is cropped with the same articles year after year with very slight variations. By and by the crops begin to fail; and the wonder is why, with such a liberal manuring every year. But it is not at all wonderful. We have seen lime, marl, sea-weed, and other fertilizers produce the most abundant crops for a few years, and then cease to have any good effect, but rather to be injurious. Thousands of gardens are defective, not from the want of manure, but from the too* frequent application of one material. People are not thoughtful or careful enough in saving the waste materials of gardens and kitchens to add to the manure heap.

The more vegetable refuse that can be returned to the garden, the less will strong animal manures be needed. Leaves, the dry stalks and waste parts of vegetables, weeds, mowings and sweepings of lawns, primings of trees, clippings of hedges, if thrown in a heap and mixed with a little manure, lime, turf from an old pasture, muck, or peat, etc., would make one of the very best composts for gardens, whatever might be the character of the soil or the crops grown on it. They return to the soil the very same substances of which it has been deprived by crops, together with others taken from the atmosphere. Such a compost is far preferable to strong stable manure, for trees especially, and may be applied with entire safety even in fertile soils, where it might be considered that manure of any kind was wholly unnecessary. The finest garden crops, and the most vigorous, healthy, and fruitful trees we know of, are those of poor cottagers who keep no animals and have no manure, but such as they scrape up in the form of refuse. Their necessities compel them to follow a system of preparing manure that every one should adopt from choice. A dressing of wood-ashes occasionally is of great value. The alkali they contain is not only useful to the soil, but destructive to grubs that infest it.

Soot is also valuable in this respect, and it is a point of some importance; for when animal manures alone have been plentifully applied for a number of years, grubs become so numerous as to render the garden nearly worthless. The best way to apply these substances is, to spread them over the ground in the fall or winter, and spade them under; before spring comes they are rendered perfectly harmless. Bones, either in a fresh state or from the glue factory, make a valuable application to gardens, and especially to fruit trees. If ground to a powder, or dissolved in sulphuric acid, they produce an immediate effect; but if simply broken in pieces, or spaded into the ground, they have a gradual and permanent effect. In taking up trees from soil where bones have been used as manure, we find every particle within reach of the roots completely enveloped in masses of fibres. Guano, superphosphate of lime, and other prepared manures, are becoming extensively used, and will be advantageous to persons who have extensive grounds to enrich, with limited means of procuring or making manure.

Those who have but small gardens have the means of making all the manure they require, and that, too, of a kind which we would prefer either to guano or any of the patent manufactured compounds.

The manner of applying manures and the time to do it require careful consideration. In this country, where we have excessive heat and often excessive drouth in summer - and that, too, at an early period of the summer - solid manures and composts of every kind should, as a general thing, be applied in the autumn; so that during winter and spring they may be dissolved and fitted to yield nutriment to plants when active growth commences. Every experienced cultivator knows that to have a good crop, or a good growth, it must be made early in the season; and therefore the supply of nutriment should be ready in abundance when growth commences and the greatest activity prevails. Solid manures applied in the spring will probably remain dry and useless all summer - and, indeed, are more likely to prove injurious than otherwise. There are, of course, exceptions to this in the case of certain garden crops of succulent nature, that may with advantage be stimulated with fresh hot manures in connection with a liberal supply of moisture. One of the best methods of maintaining the soil around trees in good condition is to apply every autumn a top dressing of compost.

The snow and rains of winter and spring dissolve and wash down its most soluble parts, and place them within reach of the roots by the time they are ready to take it up. At the same time this top dressing affords protection to the roots against the changes of temperature during the winter and spring months. There is, to be sure, some loss in this way of using composts, as a considerable portion is lost by evaporation; but its advantages are a sufficient offset.

In preparing and applying manures our aim should be first, to have it adapted, as nearly as possible, to the nature of the crops to be grown and the defects of the soil. Second, it should be applied in such quantities as the soil and the plants may require. There are certain garden crops that can scarcely be over-fed, while fruit bearing trees and many flowering plants may be ruined by excessive stimulants. Third, it should be applied at such seasons as will place it in proper condition to yield the largest amount of nutriment during the early periods of growth. These are the main points, and a volume might be written upon them. Our remarks now are merely intended to draw special attention to their importance.