THE POTATO.
The cultivation of the potato is so well understood by every American farmer and gardener that it seems unnecessary to discuss the details of cutting the tubers, planting, cultivating, harvesting, etc. The weak points of potato culture are most commonly the fertilizing and the treatment of diseases. These will be briefly discussed. As to lack of moisture, to be remedied by artificial watering, the reader is referred to our new book, entitled, "Irrigation by Cheap Modern Methods," in which a case is mentioned where water alone made a difference of 129 bushels per acre in the crop.
Potatoes.—Best for the South, Bliss Triumph, Pride of the South, Crown Jewel, Early Thoroughbred. General crop in the North—Houlton Early Rose, Table King, Late Puritan, Rural New-Yorker No. 2. For descriptions of these and other varieties, see "Johnson & Stokes' Garden and Farm Manual."
Fertilizing.—A ton of potatoes (33-1/3 bushels) contains 4·2 pounds of nitrogen (equal to 5·1 pounds of ammonia), 1·5 pounds of phosphoric acid and 10 pounds of potash. This shows that nitrogen and potash are the elements mainly abstracted from the soil by a crop of potatoes. An analysis is not an infallible index of what must be applied to any soil, for that soil may be naturally rich in some one fertilizing element and deficient in the others. Only experiment will determine what is best. But a knowledge of the analysis of the crop is necessary to intelligent experimentation. Nitrogen and potash will evidently be demanded in most cases, yet the Ohio Station recently reports that "phosphoric acid has been the controlling factor in the increase of the potato yields" in the trials made there. This shows how greatly soils vary in their requirements.
Harvesting Seed Potatoes near Houlton, Aroostook County, Maine.
Barnyard manure would answer all purposes and would be an ideal potato fertilizer, except for the fact that it so often carries with it the spores of such diseases as blight, scab and rot. Still, barnyard manure in a partly rotted condition is very widely used by potato growers.
Clover sod is an excellent source of nitrogen, as heretofore explained. The clover is, perhaps, the best of the leguminous crops for green manuring purposes. Many successful potato farmers depend largely upon clover, supplementing it with a small amount of high-grade complete fertilizer in the rows.