Fertilizers And Fertilizing
( Originally Published Early 1900's )
In gardening two factors are essential: First, a soil that is capable of absorbing and holding water without being so compact and tight as to prevent free movement of water in all directions, and, second, plant food. " Probably a typical garden soil would be a sandy loam," writes Dr. E. B. Voorhees, director of the New jersey Experiment Station. " This kind, however, would be largely regarded as a good place for the plants to grow, rather than as a source of the food required. Hence the second factor, an abundant supply of all kinds and forms of plant food needed.
" This latter may be accomplished by the use of the manures, preferably well rotted, which contain plant food in more or less soluble forms, but which possess, in addition, decaying vegetable matter, so important in contributing to the physical character of soils, more especially in the matter of holding moisture. Hence, any soil well adapted naturally for gardening should either be heavily manured or should have been subjected to green manuring for a sufficient period of time to build it up in vegetable matter.
" Owing to the. cost, both in money and labor, of supplying the food requirements through the use of manures only, nowadays resort is made to commercial fertilizers. These not only supply the total food, but are capable of supplying it in such forms as to enable the plants to absorb it at once. That is, there is no necessity for any delay, in order that the plant food constituents themselves may be made available.
" Fertilizers are, therefore, capable of supplying the needed requirements when other conditions are favorable and may be grouped into three classes, i. e., general, specific, and basic. That is, a general formula would be one that is not made for any specific crop, but which contains both soluble and insoluble forms, with the idea of building up the soil in the constituents, rather than meeting the special requirements of any one crop.
GENERAL FERTILIZER FORMULAS
" The specific formulas are those which are made up for the purpose of meeting a particular need of the crop, at a particular time, and basic formulas may be regarded as those which contain large quantities of all of the best forms of plant food. They are to be used as a base for supplying garden crops with their general needs, with the idea that amendments may be made of nitrogen, or of other constituents, as the conditions seem to require. A general formula, for exam' pie, may be made up of a mixture of, say:
Ground bone 250 lbs.
This will supply, not large quantities of nitrogen, but considerable of the minerals, and so fortify the soil in this respect. It should be applied at the rate of 50o to 1,000 pounds an acre, depending upon conditions.
"In gardening, the object is, as a rule, not only to obtain a large crop, but to have it ready as early as possible. Hence, as a rule, soil supplies of plant food are disregarded and formulas are made up and used, containing large proportions of all of the constituents and in immediately available forms, be-cause the purpose is not only to feed the plant, but to see to it that such an abundance of available food is present that under even slightly adverse conditions the plants may not suffer. That is, being in a soluble form, if dry weather comes, so long as there is any moisture in the soil, these soluble forms will be capable of feeding the plant.
" A good basic formula for such garden crops as asparagus, cucumbers, early tomatoes, onions, cabbage, cauliflower, celery, eggplants, melons, peppers, squashes, etc., may consist of :
Nitrate of soda 100 lbs.
"A mixture of these materials of standard quality would show an average composition of 5.5 per cent nitrogen, 6 per cent available' phosphoric acid, 7.5 per cent total phosphoric acid, and 7.5 per cent potash.
"In many cases it might be necessary during the growing season, particularly in the case of such crops as early beets, early cabbage, melons, and celery, to make additional dressings of nitrate of soda, preferably in fractional applications of, say, 100 pounds each. That is, the early beets, after transplanting and being properly set, should receive a top dressing of 100 pounds of nitrate of soda every ten days until 30o pounds has been applied, in addition to 800 to i,000 pounds an acre of this formula. The object of this being not only to give the plant what it needs at the time it needs it, but to guarantee the fullest use of this substance, which is so soluble that, if applied early in the season, a large proportion may be lost by washing out of the soil.
" The same is true of celery, which is not only greatly improved in quality when conditions are made favorable for rapid and continuous growth, but is also largely increased in yield. As high as 400 pounds of nitrate of soda, applied as above stated, in addition to the application of the basic formula, has proved most profitable.
" The application of these concentrated fertilizers, more especially the dressing made after the plants are growing, should be carefully made, so as not to injure the young and tender vegetation. The fertilizer should not be scattered broadcast over the plants when the foliage is wet, but rather applied along or between, the rows, and the land immediately cultivated.
" A good plan to follow is to apply the general fertilizer broadcast as soon as the land is plowed, and then worked in during the subsequent cultivation. A part of the special or basic formula may then be applied in the row, and preferably lightly covered with soil before setting the plants or seeding, and the fractional applications of nitrate, ammonia, or acid phosphate applied as before out-lined. For most garden crops there is little danger of using too much, provided the soils are in good condition, the cultivation good and the proportions of the constituents such as to provide an abundance of minerals in available forms."