CHAPTER XXVI 

 SWEET-POTATO — Ipomcea batatas 



INTRODUCTORY 



The sweet-potato belongs to the morning-glory family 

 (Convolvulacece) , which also includes a number of common 

 weeds and cultivated flowers. . This plant has long been 

 cultivated in the tropical and semitropical regions of 

 both the eastern and the western hemispheres. Its origin 

 is somewhat doubtful, but most authorities regard it as a 

 native of America. 



393. Distribution and climate. — The sweet-potato is 

 widely grown throughout the warmer regions of America 

 and Asia, as well as to a smaller extent in other countries. 

 This plant requires a warm chmate. Its culture on a 

 large scale is confined in the United States to the region 

 lying south of the line drawn through central New Jersey 

 to the southern part of Kansas. North of this fine it is 

 sometimes grown, but only on a small scale as a garden 

 vegetable and without the best results in either quahty 

 or quantity. A number of the cotton-growing states 

 each produces more than four miUion bushels annually. 



The sweet-potato grows chiefly during the hottest part 

 of the year. In contrast with the Irish potato, it may 

 be called strictly a summer crop, a difference that has an 

 important bearing on the character of fertiUzers needed 

 for these two crops. 



425 



