238 Journal of the Department of Agriculture, 



hotbed. If the ground be dry, pour in a little water and press 

 the soil down firmly around it. If the ground be moist, there 

 is no need of using the water. Plants set in this manner will 

 scarcely show that they have been moved. They should be 

 cultivated after each rain until the vines cover the ground ; they 

 will then take care of themselves. Use the cultivator between 

 the ridges. In cultivating the ridges until the plants get started, 

 I find nothing better than a common garden rake. After the 

 vines cover the ground I do not disturb them." 



In Queensland, Australia, some sweet potato growers have been in 

 the habit of planting so thickly that the ground becomes ore mass of 

 "oots and tubers, which require to be ploughed up. This was 

 condemned by the Australian Agriculturist, that journal charac- 

 terizing the practice as a method not of cultivating sweet potatoes, 

 but of filling the soil with a mass of inferior tubers. The Queensland 

 farmers were advised to plant 10 feet apart, for the reason that sweet 

 potatoes in open soil will spread their roots upwards of 10 feet each 

 way, bearing as they run, and therefore 10 feet apart for plants 

 cannot be excessive. Farmers at one time used to represent to the 

 Queensland Department of Agriculture that, although no disease was 

 apparent in the sweet potato crop, the vines failed to yield tubers.* 

 The Department attributed this failure to the common custom of 

 continuously planting the same piece of ground, and raising potatoes 

 from vines, instead of obtaining a change of roots and growing the 

 crops upon fresh ground from young shoots. The system in operation 

 was i)ronounced to be altogether wrong, having a tendency to weaken 

 the constitution of the plant. The real nature of the malady was 

 ascribed in the Annual Report of the Queensland Department to what 

 was there called '' the pernicious system of constant propagation by 

 suckers, instead of from seed." The method recommended to the 

 Qi-!eensland farmers was that about the end of July or the beginning 

 of August a few fairly large tubers of good varieties should be planted 

 and covered with not more than 2 inches of soil. These would then 

 throw up many young shoots, and when the shoots are about 6 inches 

 above ground the tubers should be lifted, and the e^/es from which 

 the young shoots spring should be carefully cut out with a sharp 

 knife. The eye with the young shoot should then be planted in the 

 ground slightly ridged, and, if the season lie at all a favourable one, 

 potatoes of good quality would be ready for lifting at least one month 

 earlier than by the method of planting a piece of the runner, and 

 the plants would be all the stronger. It maj^ be added, however, 

 that danger of transmitting disease to the new crop is less if tubers 

 from cuttings are used for seed. 



In the United States of America, where sweet potatoes are very 

 largely grown, irrigation is often resorted to with success in regions 

 of scanty rainfall, but it is recognized that the greatest caution should 

 be exercised not to apply too much water during the latter i)art of the 

 growing season, lest runners should lie formed at the expense of 

 tubers; moreover, proper ripening of the tubers is best achieved if 

 water be entirely witliheld for some time prior to harvesting. It 

 foUow'S from the above that, if it be at all possible to grow two crops 

 annually, the time of planting should be so arranged that the 



- '^ Similar occm'rences have been noticed in the Cape Province. 



