GROWING SWEET POTATOES 249 



to serve its purposes and then sweet potatoes may follow a hay or 

 grain crop just as in the practice with common potatoes. Lands 

 which receive enough moisture from below and yet are not wet 

 and cold, produce the crop with least labor and expense, though 

 it is quite feasible to proceed with direct irrigation both for plant- 

 ing and after growth. The sweet potato sends its roots to great 

 distances to find moisture. 



Growing the Plants. The sweet potato grows readily by cut- 

 tings from the growing vine planted out directly in the field if the 

 ground is moist and warm. This method is followed to rapidly 

 multiply a rare variety. The usual method is to plant the crop by 

 using sprouts from potatoes on which growth is quickly started 

 with bottom heat. Any of the hot-bed appliances described in the 

 chapter on propagation may be used for this purpose on a small 

 scale, but in the warmer parts of the state it can be done on a large 

 scale for field planting without expense of glass or cloth covering. 

 If, however, the hot-bed is used, care must be taken against over- 

 heating. 



To grow plants in the open air it is usual to begin in March 

 and dig a trench four or five feet wide and about 18 inches deep; 

 the length according to the number of plants desired. The trench 

 should be dug in light, well-drained soil, in a place protected from 

 cold winds. Put in fresh horse manure and tramp down until 

 about a foot of thickness is secured. Wet it well, but not enough 

 to drain, and immediately cover with three or four inches of sandy 

 soil. Upon this, place the sweet potatoes just as close as they can 

 be put down without touching each other. When done, sift in fine 

 sand between the potatoes and finally cover with four or five inches 

 of very sandy loam, or even with sand. Keep this bed moist but 

 not wet. Moisture and heat may be retained by covering the bed 

 with two inches of loose straw to be removed as the shoots appear. 

 The plants are ready for use in about eight weeks from the bed- 

 ding of the tubers, when they show a few green leaves; they can 

 be detached by pulling and will bring their outfit of small roots with 

 them as they are pulled out of the sand. The tubers will then send 

 up other shoots which can be planted later. 



Rather than begin in March as above stated, some begin as 

 early as February 10 and frame the bed with boards and cover 

 with boards at night to make it safe for the earlier start of plants, 

 which is thus secured. 



Some prefer to uncover the potatoes, beginning at one end of 

 the bed, removing the shoots and replacing the covering. This 

 lessens the danger of breaking the shoots. Others split the pota- 

 toes lengthwise and plant with the cut side down so that all the 

 shoots come from the upper surface and are thus less liable to 

 break in pulling. 



It takes about eight weeks for the plants to grow ready for 

 transplanting, which is done any time up to June 1 with reasonable 



