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SWEET-POTATO 



SWEET-POTATO 



Arizona and California, in spite of the fact that 

 the total heat is more than ample and the warm 

 sandy soils supply ideal conditions, with irrigation 

 water to maintain the soil moisture. Sweet-potato- 

 culture, therefore, even in the warm parts of arid 

 America is pursued commercially only at a few 

 points. Sweet-potatoes may be grown in the north- 

 ern states by careful attention, but neither the 

 quality nor the quantity of the crop is satisfactory 

 when compared with that of the South. 



According to the Twelfth Census, the sweet- 

 potato is the most extensively grown vegetable 

 in the United States, next to the Irish potato. In 

 1899 it was reported by 1,001,877 farmers, or 

 more than one-third of the number reporting Irish 

 potatoes. The acreage, including that of yams, was 

 537,447, and the value of the crop in 1899 was 

 $19,876,200. The five leading states in production 

 were North Carolina, Georgia, Virginia, Alabama 

 and South Carolina. They produced 52. 1 per cent 

 of the aggregate crop. Georgia, North Carolina, 

 Alabama, South Carolina and Texas cultivated, in 

 the order named, 70,620, 68,730, 50,865, 48,831, 

 43,561 acres, which constituted 52.6 per cent of 

 the acreage of the crop of 1899. The' acreage of 

 the south Atlantic division was 49.1 per cent 

 of the total ; the south central, 39.9 ; the north 

 central, 6.2 ; the north Atlantic, 4.5, and the 

 western division only 0.3. 



Culture. 



Climate. — The sweet-potato demands, for best 

 results, a rather warm, moist climate in the 

 growing season. An ideal season is one which has 

 frequent showers from April and May, when the 

 crop is planted, into July or early in August; then 

 when the crop is maturing in August and Septem- 

 ber, rather dry weather should follow. This is 

 particularly true of the much-grown Yellow Jersey 

 type of sweet-potato, which is retarded by drought 

 before the plants are established and requires con- 

 siderable moisture for proper growth. On the other 

 hand, cold rains on the young plants are objection- 

 able. North of the cotton-growing districts heat 

 seems to be the important and frequently lacking 

 requirement. In the cotton-belt, however, the tem- 

 perature conditions are more favorable. 



Soil. — The sweet-potato likes a warm, sandy 

 soil that is well drained and well aerated. Light 

 sandy soils may sometimes be benefited by artifi- 

 cial drainage if the subsoil is slowly pervious. The 

 highest yields are often secured on sandy knolls on 

 which corn would fire or burn, and other crops 

 suffer from lack of water. New, cleared land on 

 which a crop of corn has been grown raises fine 

 crops of sweet-potatoes. Successful crops are often 

 grown on soils that are not ideal, provided they 

 lie on hill slopes and are otherwise exceptionally 

 well drained. The red clay hills in the Piedmont 

 region of the Atlantic and Gulf states grow good 

 crops, although, as a rule, commercial cultivation is 

 not attempted on these soils. Some clays are 

 crumbly and grainy so that they allow the neces- 

 sary aeration, and the droughty character of the 

 soil may prove favorable. 



Fertilizers. — The sweet-potato is especially sus- 

 ceptible to artificial fertilizers and manures, and on 

 droughty soils where weak vine-growth is likely 

 they should be employed. Humus is essential. For 

 old land, growers sometimes haul pine leaves or 

 "woods trash" to the fields in the winter and plow 

 it under to supply humus. Light straw manure is 

 very favorable. Crimson clover sod is especially 

 valuable for this purpose when old land is to be 

 used. If used as a cover-crop, crimson clover 

 should be plowed under when it has made half its 

 growth. Cowpeas are excellent, but they disinte- 

 grate rather too rapidly ; and while the cowpea 

 land works up well in the spring, it does not retain 

 its humus through the season so well as the clover. 

 As a rule, the cowpeas should be left on the ground, 

 or perhaps, pastured by hogs, and plowed under in 

 the spring two or three weeks before planting. 

 Rye plowed under when it is just shooting into 

 head is also excellent, though by no means as good ' 

 as the clover. [See below, under Preparation of the 

 land.] 



Place in the rotation. — Sweet-potatoes do very 

 well after corn, cantaloupes, tomatoes and most 

 other field and garden crops, with the exception, 

 perhaps, of root crops. In general, planting after 

 fall-dug root crops is not to be recommended. 

 Corn, melons, tomatoes and certain other crops 

 give an opportunity for sowing crimson clover at 

 their last cultivation, and there is nothing better 

 for the sweet-potato crop than to plow under crim- 

 son clover when it is about six or eight inches 

 high. Early dug potatoes and early harvested 

 vegetable crops can be cleared from the land and 

 crimson clover sown. Cowpeas may be sown in the 

 same way, but for the later crops this is not so 

 desirable. 



With heavy manuring and fertilizing sweet- 

 potatoes can be grown on the same land for several 

 years with good results, but this practice is not to 

 be recommended. The writer has had excellent 

 crops for three years in succession, but generally 

 the second crop has been the best. This is doubt- 

 less the result of the accumulation of manure and 

 fertilizer from the previous crop. The third crop 

 begins to feel slightly the injurious effect of con- 

 tinuous cropping. One evil of successive crops of 

 sweet-potatoes on the same land is that too little 

 opportunity is afforded for cover-crops and for the 

 addition of humus. Sweet-potato vines decay so 

 completely that they add little humus to the soil. 

 With early dug sweet-potatoes, however, especially 

 toward the South, crimson clover or rye, or even 

 winter oats, can be sown to supply organic matter. 



Preparation of the land. — As a rule, yery deep 

 plowing is not best for sweet-potatoes. The com- 

 mercial demands are for a short, thick root as 

 nearly round as possible, and deep preparation, 

 though increasing the total yield, tends to make 

 long roots. On the average, five or six inches may 

 be regarded as the proper depth, although seven 

 inches would answer very well ; some growers pre- 

 fer to plow only three or four inches. The plowing 

 should be done shortly after the land comes into 

 condition in the spring ; as the sweet-potato is an 



