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Vegetable garden fertilizer


To a very small extent garden vegetables get their food from the air. The amount obtained in this way however, is so infinitesimal that from the practical standpoint it need not be considered at all. Practically speaking, your vegetables must get all their food from the garden soil.

This important garden fact may seem self-evident, but, if one may judge by their practice, amateur gardeners very frequently fail to realize it. The professional gardener must come to realize it for the simple reason that if he does not he will go out of business. Without an abundant supply of suitable food it is almost impossible to grow good vegetables. Without plenty of plant food, all the care, coddling, coaxing, cultivating, spraying and worrying you may give will avail little. The soil must be rich or the garden will be poor.

Plant food is of as many kinds, or, more accurately speaking, in as many forms, as is food for human beings. But the first distinction to make in plant foods is that between available and non-available foods - that is, between foods which it is possible for the plant to use, and those which must undergo a change of some sort before the plant can take them up, assimilate them, and turn them into a healthy growth of foliage, fruit or root. It is just as readily possible for a plant to starve in a soil abounding in plant food, if that food is not available, as it would be for you to go unnourished in the midst of soups and tender meats if the latter were frozen solid.

Plants take all their nourishment in the form of soups, and very weak ones at that. Plant food to be available must be soluble to the action of the feeding root tubes; and unless it is available it might, as far as the present benefiting of your garden is concerned, just as well not be there at all. Plants take up their food through innumerable and microscopic feeding rootlets, which possess the power of absorbing moisture, and furnishing it, distributed by the plant juices, or sap, to stem, branch, leaf, flower and fruit. There is one startling fact which may help to fix these things in your memory: it takes from 300 to 500 pounds of water to furnish food for the building of one pound of dry plant matter. You can see why plant food is not of much use unless it is available; and it is not available unless it is soluble.

The food of plants consists of chemical elements, or rather, of numerous substances which contain these elements in greater or less degrees. There is not room here to go into the interesting science of this matter. It is evident, however, as we have already seen that the plants must get their food from the soil, that there are but two sources for such food: it must either be in the soil already, or we must put it there. The practice of adding plant food to the soil is what is called manuring.

I have tried to present this matter clearly. If I have succeeded it may have been only to make the reader hopelessly discouraged of ever getting at anything definite in the question of enriching the soil. In that case my advice would be that, for the time being, he forget all about it. Fortunately, in the question of manuring, a little knowledge is not often a dangerous thing. Fortunately, too, your plants do not insist that you solve the food problem for them. Set a full table and they will help themselves and take the right dishes. The only thing to worry about is that of the three important foods mentioned there will not be enough: for it has been proved that when any one of these is exhausted the plant practically stops growth; it will not continue to "fill up" on the other two. Of course there is such a thing as going to extremes and wasting plant foods, even if it does not, as a rule, hurt the plants.

The terms "manure" and "fertilizer" are used somewhat ambiguously and interchangeably. Using the former term in a broad sense - as meaning any substance containing available plant food applied to the soil, we may say that manure is of two kinds: organic, such as stable manure, or decayed vegetable matter; and inorganic, such as potash salts, phosphatic rock and commercial mixed fertilizers. In a general way the term "fertilizer" applies to these inorganic manures, and I shall use it in this sense through the following text.

Between the organic manures, or "natural" manures as they are often called, and fertilizers there is a very important difference which should never be lost sight of. In theory, and as a chemical fact too, a bag of fertilizer may contain twice the available plant food of a ton of well rotted manure; but out of a hundred practical gardeners ninety-nine - and probably one more - would prefer the manure. There is a reason why - two reasons, even if not one of the hundred gardeners could give them to you. First, natural manures have a decided physical effect upon most soils (altogether aside from the plant food they contain); and second, plants seem to have a preference as to the form in which their food elements are served to them. Fertilizers, on the other hand, are valuable only for the plant food they contain, and sometimes have a bad effect upon the physical condition of the soil.

When it comes right down to the practical question of what to put on your garden patch to grow big crops, nothing has yet been discovered that is better than the old reliable stand-by - well rotted, thoroughly fined stable or barnyard manure. Heed those adjectives! The plant food in "green" or fresh manure is not available, and does not become so until it is released by the decay of the organic matters therein. Now the time possible for growing a crop of garden vegetables is limited; in many instances it is only sixty to ninety days. The plants want their food ready at once; there is no time to be lost waiting for manure to rot in the soil. That is a slow process - especially so in clayey or heavy soils. So on your garden use only manure that is well rotted and broken up. On the other hand, see that it has not "fire-fanged" or burned out, as horse manure, if piled by itself and left, is very sure to do. If you keep any animals of your own, see that the various sorts of manure - excepting poultry manure, which is so rich. If you have to buy all your manure, get that which has been properly kept; and if you are not familiar with the condition in which it should be, get a disinterested gardener or farmer to select it for you. When possible, it will pay you to procure manure several months before you want to use it and work it over as suggested above. In buying manure keep in mind what animals made it, and what food was fed - that is the important thing. For instance, the manure from highly-fed livery horses may be, weight for weight, worth three to five times that from cattle wintered over on poor hay, straw and a few roots.

There are, however, numerous things constantly going to waste about the small place, which should be converted into manure. Fallen leaves, grass clippings, vegetable tops and roots, green weeds, garbage, house slops, dish water, chip dirt from the wood-pile, shavings--any thing that will rot away, should go into the compost heap. These should be saved, under cover if possible, in a compact heap and kept moist (never soaked) to help decomposition. To start the heap, gather up every available substance and make it into a pile with a few wheelbarrows full, or half a cartload, of fresh horse manure, treading the whole down firmly. Fermentation and decomposition will be quickly started. The heap should occasionally be forked over and restacked. Light dressings of lime, mixed in at such times, will aid thorough decomposition.

Wood ashes form another valuable manure which should be carefully saved. Beside the plant food contained, they have a most excellent effect upon the mechanical condition of almost every soil. Ashes should not be put in the compost heap, because there are special uses for them, such as dusting on squash or melon vines, or using on the onion bed, which makes it desirable to keep them separate. Wood ashes may frequently be bought for fifty cents a barrel, and at this price a few barrels for the home garden will be a good investment.

Coal ashes contain practically no available plant food, but are well worth saving to use on stiff soils, for paths, etc.

Another source of organic manures, altogether too little appreciated, is what is termed "green manuring" - the plowing under of growing crops to enrich the land. Even in the home garden this system should be taken advantage of whenever possible. In farm practice, clover is the most valuable crop to use for this purpose, but on account of the length of time necessary to grow it, it is useful for the vegetable garden only when there is sufficient room to have clover growing on, say, one half-acre plot, while the garden occupies, for two years, another half-acre; and then changing the two about. This system will give an ideal garden soil, especially where it is necessary to rely for the most part upon chemical fertilizers.

There are, however, four crops valuable for green-manuring the garden, even where the same spot must be occupied year after year: rye, field corn, field peas (or cow peas in the south) and crimson clover. After the first of September, sow every foot of garden ground cleared of its last crop, with winter rye. Sow all ground cleared during August with crimson clover and buckwheat, and mulch the clover with rough manure after the buckwheat dies down. Sow field peas or corn on any spots that would otherwise remain unoccupied six weeks or more. All these are sown broadcast, on a freshly raked surface. Such a system will save a very large amount of plant food which otherwise would be lost, will convert unavailable plant food into available forms while you wait for the next crop, and add humus to the soil.