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(Courtesy New Jersey Department of Conservation and Development)Soil is created from rock by nature’s weathering processes and by plant growth.At the bottom may be seen solid rock; just above are disintegrating rock fragments, and at the top, the soil.
Every type of real soil contains all the elements of plant growth. This plant food results from a breaking down of soil particles and the setting free of chemical elements which, either singly or in combination, serve as food for plants.
Whatever the type of soil may be, it will be found that certain crops will make better growth in it than others. As a general rule, it may be said that the only way to determine which plants will grow best on a given soil is by the trial-and-error method. However, by observation of the growth on similar types of soil we can learn something of a soil’s crop adaptability. There are some crops that will grow in almost any soil and there are others that need an exactness of texture, moisture and plant food which makes them highly specialized products. The operator must learn how to work in harmony with the peculiarities of his own soil before he can hope to get the best results.
In acquiring a tract for the growing of plants of any kind it is desirable to get a soil type that will meet the requirements of most plants. As a general rule, this type contains enough clay to be retentive of moisture, enough sand to be easily worked and is generally suitable for bacterial growth. In other words, what is commonly called a loam is the ideal type for general agricultural and horticultural purposes. This may be a heavy loam, in which clay predominates, or a so-called light loam, in which sand particles predominate. An examination of a handful of soil by a person experienced in farming will indicate its nature and its adaptability to ordinary crop production.
Essential Elements of Plant Food.—Countless scientific experiments in plant growth show that potassium, lime, phosphorus, magnesium, iron, sulphur, nitrogen, carbon, oxygen and hydrogen are essential to normal development. The carbon, hydrogen and oxygen elements make up nearly 99 per cent of the entire composition of the plant and are derived from the atmosphere. All of the other elements are derived from the soil except in the case of peas, beans, clovers and other legumes which secure most of their nitrogen from the air.
The mineral elements are not needed in large amounts but well-balanced plant growth isstrictly dependent upon their presence in available form. Of these elements, those most likely to be deficient either in total amount or in availability are nitrogen, phosphorus, potassium and calcium. It is entirely feasible and economical to apply concentrated chemical fertilizers containing the first three elements so that their lack will not constitute a limit to size of crops harvested. In many cases it is necessary to apply chemical fertilizers to get satisfactory yields, even where natural manures are available and can be applied as well.
In addition to supplying essential plant food, nitrogen, phosphorus and potassium perform specific functions in plant growth. The application of nitrogen in one of its readily available forms (e.g., nitrate of soda and sulphate of ammonia) will stimulate vegetative growth. If too much of this one element is applied, leaf and branch development may occur at the expense of the crop. Good results follow the use of nitrogen on grass sods and on leafy vegetables like spinach. On the other hand, corn, peas, beans and other seed-forming crops need to have the nitrogen balanced with phosphorus. Potatoes, in common with other tuber and root crops, will utilize plenty of potassium in the development of starch.
Sources of Plant Food.—Chemical fertilizers can be purchased at supply stores in readymixed condition and of analyses that will meet general crop needs. A good formula for such a general purpose fertilizer is 4 to 5 per cent nitrogen, 7 to 9 per cent phosphoric acid and 7 to 10 per cent potash to the ton. It is known that such a mixture will supply the food needs of a large variety of plants in balanced amounts. Highly concentrated mixtures are now on the market providing double the amount of plant food in the example quoted, costing nearly twice as much but effecting a saving by cutting in half the material handled to get the same result. Care should be taken, in using these highly concentrated fertilizers, to avoid contact with tender roots. A mixture for general farm and garden purposes may contain the following ingredients:
This mixture will have a formula of 4-9-7 (4 per cent nitrogen, 9 per cent phosphoric acid and 7 per cent potassium). The individual who wishes to mix his own fertilizer may do so by purchasing the finely ground ingredients separately, and by means of a shovel, integratethem all into a mixture. Home mixing will not be found profitable where small amounts of fertilizer are used. Those who practice home mixing for the first time should realize that most combinations of ingredients will “set” or harden if not used immediately, necessitating the breaking up and pulverizing of the mass. When it is broken up after curing, no further difficulty should be experienced with “setting” if the mixture is kept in a dry place. The advantages of home mixing for the large user lie in lower cost per ton of plant food as a rule; confidence in the quality of the ingredients which he should purchase on the basis of guaranteed analysis; and the setting up of a mixture which study of his soil and the plant requirements has convinced him is best suited for his individual case.
Chemical Soil Analysis Not Helpful.—There is a mistaken notion that it is necessary to analyze soils chemically in order to fertilize them intelligently. Such an analysis of a reasonably fertile soil will show the presence of the essential elements of plant food, though perhaps not all in sufficient amounts, to produce ordinary crops for centuries to come. Only a small amount of the elements become available for root absorption each year and a chemical analysis will not bring out this most important factor—availability. The use of a few simpletests, mainly of a physical nature by a competent soils specialist, will prove of some assistance in the treatment of the soil. Such tests will show the presence of adequate amounts of humus, and indicate the acidity content. The soil texture will give some index of its crop adaptability and thereby serve as a basis for fertilizing treatment that will meet the needs of both soil and crop. The practical man will not expect any considerable aid from a highly technical and costly chemical analysis of his soil.
Another factor that militates against worth-while benefits of chemical soil analysis is the great variation in soil types frequently occurring in the same field. To attempt to draw a representative sample by mixing soil from several areas might result in a specimen that would not be really typical of any area. For the purpose of ordinary physical examination and testing for acidity, representative soil samples should be taken from several parts of the same soil type, mixed together and a composite sample for testing drawn from the mixture, weighing not less than a pound in each case. If the soil is quite apparently variable it may be necessary to draw two or more composite samples from the same area. Very helpful service in intelligent soil treatment may besecured from the county agricultural agent and the state college of agriculture in the county or state of residence.
Legumes as Soil Improvers.—A means of soil improvement that is well understood by progressive farmers is the use of legumes to improve the soil. The legumes include a large family of plants of which the bean, the pea and the clovers are outstanding examples. Such plants have on their roots nodules which house nitrogen-gathering bacteria. These bacteria absorb nitrogen from the air in the soil and, in the ordinary process of growth, death and decay, make this nitrogen available to the host plants, leaving a residue in the soil for the roots of plants that are to follow. Thus this group of plants, known as legumes, have been used for generations as a method of increasing the nitrogen content of soils. Nitrogen, incidentally, is the most costly element to buy in commercial fertilizers. The soil-improving benefits of legumes may be secured by growing them either for harvest as a source of animal food or for plowing under as a means of utilizing them entirely for the development of soil fertility.
In reading of the studies of soil fertility that were made by George Washington at Mount Vernon, we learn of the improvement that he made in the relatively poor soils of that area bygrowing plants of the legume family. The actual reason why such improvement was brought about was not known in Washington’s time, but the results were apparent. Today, the value of legumes as soil builders is well recognized and we understand much more definitely than Washington did the reasons for their being so helpful in increasing crop production.
Many soil areas do not contain the particular type of bacteria necessary to the fixation of atmospheric nitrogen by legumes. This is frequently the cause of failure in growing alfalfa, soybeans, cowpeas and less well known members of the legume family. Each legume has its own type of nodule-forming bacteria. In order to assure the presence of the proper bacterial family, means often must be employed to add them to the soil where the specific crop is to be grown. This may be accomplished by adding soil from an area where the legume does well to the new area, or the seed may be inoculated with commercial cultures before seeding. Either method is effective. If soil is used it should be drilled in or spread on a cloudy day to prevent the destructive action of the sun’s rays on the exposed minute forms of plant life we call bacteria.
If it is not known that the legume to be planted has been grown successfully in a given fieldwithin the previous several years, the precaution of adding the proper bacteria should be taken. In some sections, such legumes as red, alsike, crimson and white clovers have been grown for many years and the bacteria for these plants are well distributed. There, inoculation is not necessary for these crops, but it probably should be practiced if other legumes such as alfalfa, cowpeas or soybeans are to be grown on land for the first time.
The Value of Humus.—In addition to the chemical elements of plant food, all productive soils contain decaying vegetable matter, generally classified under the term “humus.” Humus serves as a source of acid-generating material which further breaks down soil particles and, most important of all, serves as a food for millions of microscopic plants which develop and die quite beyond the scope of human vision. These constitute a type of bacteria which are distinctly beneficial and essential to human life since they make possible the growth of larger plants that serve as human food.
Green plants, straw or leaves, when plowed under or spaded in the soil, are attacked by bacterial agencies which gradually turn these products into humus. The same process occurs when a “compost” is set up. This is made of leaves, manure, soil, straw and other materialsthrown into a heap and allowed to decay. Such compost is excellent for placing around plants when setting them out, since it holds moisture, supplies fertility and creates optimum conditions for young root growth. Under practical field conditions, humus may be added to soils by spreading animal manures, followed by plowing them down, or by the growing of heavy green crops such as wheat, rye, cowpeas or vetch and turning the entire mass under with the plow when they are at their height.
Lime and Its Application.—Reference has been made to the fact that calcium is an essential plant food and is frequently deficient in soils. As a matter of fact, the great majority of soils are deficient in calcium and their productiveness is inhibited thereby. Lime supplies calcium and also magnesium as food for plants. Its application accomplishes many other desirable things such as correcting soil acidity. The growth of beneficial bacteria is greatly stimulated in a soil that has had its acidity neutralized by the application of lime. This product, therefore, creates a more congenial condition for the growth of bacteria, which, in turn, make for better crop production. Lime is also beneficial through furnishing the element calcium with which other plant foods combine chemically and thereby become soluble in the soil water. Unless plant foods are in astate of solution, they cannot be absorbed by plant roots. Lime is a potent force in creating chemical reactions in the soil, resulting in the stimulation of growth through increased absorption of essential elements in solution.
Lime also benefits soils of a clayey nature through its ability to cement together the fine clay particles and in that way create air spaces so greatly needed in tight clay soils. Lime is beneficial, too, in the case of soils which have a large proportion of sand or large particles, and serves as an agent in creating a better condition of tilth and of moisture retention.
It makes little difference in what form lime is applied. It may be purchased and applied in the form of ground limestone, a rock rich in calcium which has been mechanically ground to a very great degree of fineness. It can also be applied in the form of hydrated lime. This is obtained by heating ground limestone and slaking it by adding water. A common example of this is the slaking of lime for whitewashing purposes. Another good source of lime is finely ground shells of oysters or other forms of sea life which collect the calcium from sea water and deposit it in their shells.
Adjusting the Water Content of Soils.—Aside from the supplying of water by irrigation, a rather costly process under most conditions,the water resources of most soils can be greatly increased by adding to their humus content. Humus, which, it has been pointed out, is decaying vegetable matter, serves as a sponge for the absorption of soil water and for underground water supplies. Therefore, the more humus that can be plowed into the soil, other conditions being equal, the greater is the ability of the plants growing in that soil to withstand drouth. As soils are cultivated, the tendency is for the humus to become “burned out” and to have a reduced moisture-holding capacity. To overcome this tendency, it is necessary to add vegetable matter to the soil whenever it is possible. Incidentally, the incorporation of large quantities of humus in the soil creates a condition of acidity which may call for the application of lime as a corrective.
There are many acres of land which contain too much water in the area that roots should penetrate to permit of optimum plant growth. Roots of most plants will not penetrate where there is an excess of water, and air cannot circulate where moisture is superabundant. Usually these conditions exist where the soil is of a clayey nature. The abundance of water may be caused by the inability of surface water to percolate through the soil. It may take so long, due to the nature of the soil, for this water topass through the lower depths of subsoil that the roots of plants are destroyed by lack of oxygen. In such cases the application of lime, increasing the humus content, and deeper plowing will be found helpful. Occasionally, the discharge of dynamite or blasting powder in the area, if it appears to be in the form of a pocket, will break up the hard pan subsoil and permit the water to escape. Less dependence is now being placed on this means of correcting a wet condition of the soil than was the case some years ago.
A similar condition of overabundant water in soil may be due to the presence of springs or to a high water table. Little can be done to correct a condition where the water table itself is so close to the surface as to inhibit plant growth and this is assuredly one of the factors to be looked into before a tract is purchased. Where the surplus water is evidently being supplied by a spring, an underdrain made of tile pipe, 3 or 4 inches in diameter, can be laid as a means of conducting the water into a ditch or adjoining drain. In laying such a drain, it should be placed above the area where the wet soil surface is most evident. If such a drain is laid 18 inches to 3 feet deep above the wet area, it will cut off the water seeping down underground and carry it away. Good results cannotbe secured if the drain is laid directly in the area of extreme wetness or if it does not cut off the flow of water before it reaches the area that is consistently too wet for plant growth.
From what has been said in this brief description of soil treatment and soil improvement, it is evident that one must live with his soil for some time in order to understand it and to be able intelligently to correct its deficiencies, overcome its weaknesses and make it capable of supporting plants which are desirable from the owner’s point of view. In the great majority of cases, the improvement process, while a slow one, is far from hopeless and almost any soil that is not extremely sandy or clayey can be so intelligently treated as to make it productive.
Cultivation.—Any discussion of soil treatment is not complete without mention of cultivation. Intelligent cultivation is an essential factor in securing adequate crops. It is interesting to recall that the word “manure,” which has come to mean fertilization or fertilizer, is derived from the Latin word “manus” meaning “hand” and implying “manipulation” of the soil, which we now call cultivation. Cultivation has been most frequently practiced as a method of destroying weeds, thereby making all of the available plant food subject to absorption bythe roots of the desired plants and not by the intruders we call weeds. Cultivation does more than destroy weeds, however. It opens up the soil so that air containing atmospheric nitrogen can penetrate it and so that the bacteria requiring air for their best growth may have it available. Furthermore, cultivation conserves moisture and is more essential during dry periods in the growing season than at any other time.
We know that in entering the soil the rain water follows certain channels in and around the soil particles on its way to the subsoil. When the rain has ceased and the top layer of soil becomes dry, the tendency is for the water to work up through these same channels to the surface, where it evaporates. Cultivation, by breaking up these channels, or capillary tubes, checks the escape of moisture into the air. It creates a blanket of dry surface soil which insulates the soil moisture from the air above. The tendency of soil moisture to reestablish capillary methods of escape makes recultivation necessary from time to time in dry weather. Care must, of course, be taken that the cultivation is not harmful to roots of growing plants. If these roots are disturbed or destroyed through cultivation, more harm than good may result because of the damage to the root systems.
Farm Power and Equipment.—Where the land area to be cultivated is larger than the family garden some type of equipment for working the land, propelled by horse or motor, will be found desirable and in larger areas essential. One or more horses may be used where there are stabling facilities and where arrangements can be made for the daily care and feeding that these animals require. A horse suitable for work purposes may be obtained for less than $200. The price will, of course, depend upon the age and physical soundness of the animal, but should not exceed $150 for a physically sound animal under ten years old. A person unskilled in the assessing of animal values should obtain the services of a veterinarian or an experienced horseman in making a selection. A horse for this purpose should be of quiet, tractable disposition, bred and broken for work purposes. The cost of caring for a horse for one year will approximate $125, including feed and bedding, but without labor charge.
Leather harness costing $25 to $50 will be required and in addition tools, including a plow, a harrow, and a cultivator costing about $15 each. Other special equipment such as a mower will cost considerably more, depending upon the type used.
If the members of the family are fond of animals and willing to assume the responsibility for their daily care, the horse will be found an efficient and useful source of power for tilling the land. In this connection it should be pointed out that flies breed with great rapidity in the strawy manure of the stable, and such wastes should be spread upon the land almost daily or treated to prevent fly-breeding.
Tractor Power.—Just as large tractors have supplanted horses and horse-drawn equipment on thousands of farms in the United States, the so-called garden tractor has become increasingly popular for the tilling of small acreages. The tractor requires “feed” only when it is working, is not subject to the ills that beset animals, and may be used for twenty-four hours a day if necessary. It makes an appeal to the mechanically minded members of the household and, if properly cared for, will give economical and lasting service.
The usual type of garden tractor consists of two large wheels with lugs on them to give traction and is driven by a one- or two-cylinder motor. A plow, a cultivator, or mower may be attached to the drawbar, the operator walking behind and regulating the speed and guiding the outfit by handles provided for the purpose. Earlier types of these machines were not alwayssatisfactory owing to construction weaknesses and occasionally balky motors. Those now on the market, however, are greatly improved, require less attention, and rival their big brothers, the powerful farm tractors, in dependability.
There are a number of types and makes of garden tractors now on the market, ranging in price from $175 or less to $400, the cost depending largely upon the size and capacity of the motor. In selecting a satisfactory garden tractor attention should be directed to the simplicity and power of the motor, the type of bearings, the method of lubrication of all moving parts, the working speed and the economy of fuel. Bearings ought to be of standard, long-wearing type since these are subject to hard service. Two speeds are desirable, a slow one for heavy duty and a faster one for lighter work. The tractor should operate all day on about 2 gallons of gasoline and a quart of oil. In addition to power applied at the drawbar where special tools are attached, a pulley will be found a desirable accessory for operating belt machinery such as small feed mills, pumps, and cream separators. The rating of the motor should be not less than 3 horsepower at the drawbar for the ordinary tasks it will be called upon to perform.
All types of attachments are available for the garden tractor. These include plows, disks,harrows, cultivators, mowers, fertilizer distributors, planters, sowers and seeding accessories. The prices of these vary according to make and quality. Levers are provided for adjusting the depth of plowing, cultivating and seeding. Some of the large type garden tractors are equipped with a seat on a sulky attached to the machine so that the operator can ride and have complete control over speed and the type of work he wishes to do. A modern garden tractor will be found very useful in taking care of a lawn or garden. In the case of larger areas under cultivation, but not of field size, this type of machine is rapidly gaining popularity for performing efficiently and economically the numerous jobs that are to be done on every small farm.
Do’sSelect a soil type that is inherently productive, fertile, retentive of moisture and easily cultivated.Supplement soil fertility by adding chemical fertilizers either singly or in combination.Buy mixed fertilizers on the basis of guaranteed analyses.Use legumes (peas, beans, etc.) to add nitrogen to soils and increase humus content.Add specific bacteria for the production of various legumes.Use manure and green crops to supply humus.Apply lime when soil test shows need for it as plant food and general soil improver.Practice methods that make soils absorptive of moisture and permit escape of excess water.Cultivate the soil to check escape of moisture and to kill weeds.Use a horse or garden tractor for cultivation of areas larger than the family garden.Don’tsDon’t buy land that is continually wet and swampy.Don’t expect to produce satisfactory crops on soils that are extremely heavy or clayey or so sandy as to quickly lose moisture and fertility.Don’t try to produce crops without maintaining the humus supply in the soil.Don’t neglect cultivation as a means of conserving moisture, destroying weeds and stimulating root growth.
Do’s
Select a soil type that is inherently productive, fertile, retentive of moisture and easily cultivated.
Supplement soil fertility by adding chemical fertilizers either singly or in combination.
Buy mixed fertilizers on the basis of guaranteed analyses.
Use legumes (peas, beans, etc.) to add nitrogen to soils and increase humus content.
Add specific bacteria for the production of various legumes.
Use manure and green crops to supply humus.
Apply lime when soil test shows need for it as plant food and general soil improver.
Practice methods that make soils absorptive of moisture and permit escape of excess water.
Cultivate the soil to check escape of moisture and to kill weeds.
Use a horse or garden tractor for cultivation of areas larger than the family garden.
Don’ts
Don’t buy land that is continually wet and swampy.
Don’t expect to produce satisfactory crops on soils that are extremely heavy or clayey or so sandy as to quickly lose moisture and fertility.
Don’t try to produce crops without maintaining the humus supply in the soil.
Don’t neglect cultivation as a means of conserving moisture, destroying weeds and stimulating root growth.
The homevegetable garden should supply an important part of the food for every family living in the country. Vegetables that are of the right varieties and that are fresh and properly prepared are nutritious, wholesome and economical. Not only does the well-organized home garden reduce the cost of feeding the family, but it constitutes an effective method of maintaining better health among all members of the household. Even common vegetables that are grown from the best varieties and served fresh will be a revelation to those accustomed to buying them in stores. Deterioration in quality and palatability begins immediately in vegetables when they are harvested. The more perishable the commodity, the greater is the rate of deterioration.
The commercial vegetable grower usually inclines toward varieties that are capable of producing a heavy yield per acre or that stand shipment and temporary storage with the least apparent loss from deterioration. In order tohave his products reach the consumer in an attractive condition, the commercial grower usually must harvest them before they are at their best. The channels through which vegetables and fruits pass on their way to the city consumer are devious, slow and costly. Such a consumer therefore usually receives so-called fresh products that have been removed from the plant or the soil before maturity is attained and after such already poor quality has deteriorated through aging processes.
All these disadvantages of vegetables purchased in the city are eliminated by the possessor of a garden where he may produce his family’s needs (and they are genuine needs) in the way of fresh vegetables. These products are essential in supplying such necessary elements as minerals, vitamins, acids, and cellulose. Dietary authorities advise that leafy vegetables, sometimes called “greens,” contain food elements not found in root vegetables. For the maintenance of health, the diet should include a variety of vegetables besides potatoes.
Assets of a Garden.—A garden is a source of recreation, pleasure and satisfaction to every member of the family. Real enjoyment can be had by working in it a little time each day. To those whose work may be sedentary and of a routine nature, the garden furnishes a sourceof inspiration and adventure. Daily evidences of plant growth and the novelty of having vegetables of one’s own growing stimulate interest in it. The garden is an aid in maintaining health through physical exercise and the liberal consumption of the fruits of labor. There is no other avenue of activity that can afford so much in the way of health, economical recreation and pleasure as a well-planned garden.
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(Courtesy New Jersey Agricultural Extension Service)The well-planned garden furnishes food throughout the year for the entire family.
Having decided on a garden, the question immediately arises as to the procedure to be followed to get the most out of it. Special attention has been given to this problem by experts throughout the country and specific recommendations are now available on the subject at state agricultural colleges. These cover varieties, planting dates, adequate area, fertilization, rotation of crops and storage. Typical recommendations along these lines are given here for the north-central and eastern states. Readers living elsewhere may wish to check them with the practices recommended by authorities in their home states.
Vegetable Growing by Rule.—The most effective method of presenting the story of recommended vegetables, desirable varieties, seed required, average yields and other pertinent data is in tabular form, such as that used in Table I, which has been prepared for the aid of homevegetable gardeners by the New Jersey Agricultural Experiment Station, and which is based on years of study of the subject. Table II, prepared by the Michigan State College of Agriculture, shows the amount of seed that should be purchased to supply an adequate quantity and variety of important vegetables for a family of six persons.
Examination of the planting table will show that the setting of plants or roots is occasionally recommended instead of the use of seed. This is desirable in some cases to get quicker results and in other cases is essential if a crop is to be secured during a normal growing season. While it is possible for the grower to raise these plants, or sets, himself, usually more satisfactory results can be obtained through buying them from a capable plant grower. The growing of sets is a specialized business requiring conditions of heat, moisture, fertility and skill, frequently beyond the patience and capacity of the amateur. There are plant growers in nearly every neighborhood who will grow the needed plants at small cost. Arrangements should be made in advance for growing the varieties or strains that are wanted, and usually the grower can furnish his own seed for the plants if that seems desirable to him. One desiring to grow one’s own plants from seed can secure full information from a practicalgrower or from state and county agricultural agencies.
Table I
PLANTING TABLE FOR VEGETABLES[1]
Table II
AMOUNT OF SEED TO PURCHASE FOR FAMILY OF SIX[2]
Planning and Operating a Home Garden.—In planning the home vegetable garden there are a few essential points to be kept in mind. The time to plan the garden is in winter when adequate consideration can be given to the selection of those vegetables that the family likes best and can use in large amounts. Seeds required should be ordered early for the entire garden. By drawing the plan of the garden on paper and following it, the procedure is simplified and the most efficient results attained.
Vegetables should be planted in rows rather than in beds, and those maturing at about the same time should be grouped together to facilitate succession planting. After the early-maturing crops have been harvested, other crops can be sown on the same area, thus fully utilizing the land throughout the growing season. Perennial crops, including asparagus and rhubarb, should be kept by themselves.
A practical farmer wanting to express perfection in soil preparation is apt to say, “It is just like a garden.” This implies good fertility, optimum moisture conditions and proper tilth. To attain these conditions in garden soil it is desirable to cover it with strawy manure some time previous to plowing, in order that rains maycarry the soluble fertility elements into the surface inches of the soil. In the early spring a thorough job of plowing or spading should be done to reasonable depth, completely covering the surface straw or dead plants. Every two or three years lime should be applied after plowing and worked into the top soil at the rate of 1 pound of hydrated lime to every 25 square feet of soil.
Fertilizing and Culture.—The fertility supplied through application of manure should be supplemented by the use of commercial fertilizer. This can be purchased in burlap bags from local supply agencies and should contain about 5 per cent nitrogen, 8 per cent phosphoric acid and 7 per cent potash. Moderate variations in analysis from 5-8-7, as above, are not important so long as the amounts of each element are well balanced. The fertilizer should be broadcast over the garden after plowing, at the rate of 1 pound to every 25 square feet and worked into the soil before planting. Poultry or sheep manure may be used as top dressing to alternate with commercial fertilizer. It should be borne in mind that such animal manures are richer in nitrogen than in other elements and if used to excess may stimulate leaf growth at the expense of yield and quality.
Frequent shallow cultivations are desirable. The ordinary wheel hoe will be found helpfulin the cultivating procedure. It should be well understood that cultivation is essential to prevent weed growth and conserve moisture.
If watering or irrigating is necessary in dry weather, it should be thoroughly done. One soaking of the soil to a depth of 4 to 6 inches is far more effective than frequent light sprinklings. The latter may be more harmful than beneficial through reestablishing capillary movement, permitting the escape of subsoil moisture. Water should be applied under the same conditions that apply when rain falls—on cloudy days or after sunset to prevent “baking” or encrusting of the surface soil as well as to conserve the amount of water needed.
Meeting the Insect Problem.—The sponsor of a garden in which diversified vegetables are grown must be prepared to meet the onslaught of equally diversified insect species. While it is true that insects are multiplying as to species and voraciousness, it is equally true that methods of control are becoming available to cope adequately with most of them. One unfamiliar with our insect infestations will be amazed to find that certain species apparently have had advance notice of his intentions and are sitting about the planted rows awaiting the appearance of the tender shoots.
One of the best methods of combating insects is to create ideal conditions for plant growth.Plants that are underfed through inadequate soil fertility or are weakened by other causes suffer severely from insect attack, while vigorous plants will come through with much less damage. It is advisable to insure rapid germination of seed through careful soil preparation, to seed at the proper time for a quick and vigorous start and to have sufficient available fertility to stimulate growth once the plants have started.
There are two distinct classes of insects, the division being based upon their feeding habits. The larger group, both in the size of the insects themselves and in the number of species, is the leaf-chewing group. These can be destroyed by the application of stomach poisons to the plants under attack. The other group consists of the sucking insects, which penetrate the veins carrying nourishment to the leaves and appropriate it for themselves. Such insects multiply with extreme rapidity, generally feed on the underside of the leaves and may cause complete wilting of the plant before their presence is suspected. In such cases a “contact” spray or dust must be used. This is based on the principle of causing the insect to “inhale” the material through breathing pores along its body. The insecticide must be composed of extremely fine particles or must be of such an oily naturethat it will readily penetrate such pores. In addition to these, certain repellent materials are being developed which cause the insect to seek food where the disagreeable conditions do not prevail.
Table III
PRINCIPAL INSECTS AND REMEDIES[3]
Table III (pages 107-108) describes the character of damage done by both groups of insects, the plants attacked and the most effective methods of control.