ROOT CROPS 525 



A point of very great importance when planting by either method is to 

 see that the soil is thoroughly compacted around the plant. This is especially 

 necessary in dry weather. When the plants are dibbled, this compacting is 

 done by the man pressing the soil 'firmly against the plant with his foot. 

 Winn ploughed in, a heavy roller with a large diameter should follow the 

 planting. A roller with a small diameter will drag the plants up. Whatever 

 method of planting is adopted, if the ground be at all moist, the plant will 

 root without difficulty. 



It is the practice of some growers to plant on ridges. In cold districts 

 this is probably beneficial, but at the College satisfactory results have always 

 been obtained without the trouble and expense of ridging. 



After-cultivation. 



The subsequent cultivation given to this crop is such as will keep the 

 weeds down and conserve moisture. Cultivation with a small-toothed 

 scuffler may commence as soon as the plants are set out, and can be continued 

 until the vines cover the ground. Other than disturbing the vines whilst 

 cultivating, no attempt is made to prevent them rooting where they touch 

 the ground. 



Harvesting. 



Plants set out early in October should produce tubers fit for the table 

 by the end of December. This time, however, will be determined by the 

 nature of the season. In a forward season sweet potatoes fit to eat may be 

 available before Christmas, but in a cool year the earliest potatoes may not 

 be ready until the middle of January. 



The mature stage can be determined by cutting one of the potatoes. If 

 the cut surface dries white and does not turn greenish-black round the edge, 

 the potato is fit to eat. If a milky juice exudes which, on exposure to the 

 air, turns black, the potato is not mature enough. 



The potatoes will continue to grow until the first frost is experienced; 

 this destroys the vines, and, of course, the tubers will cease to grow after 

 this. The crop may be left in the ground until then, and, if the frosts 

 are not very severe, they may be left until they are required, but the vines 

 should be removed, or when they decay they will communicate rot to the 

 tubers. 



During the last two months of the growing season the yield per acre is 

 very much increased; in some cases it almost doubles itself. Where, 

 therefore, bulk is a desideratum it is well to leave the tubers in the ground 

 for as long as possible after they become fit for the table. 



The harvesting is usually done by hand labour. Some diggers prefer to 

 use a pronged hoe, others a digging fork; it is a question of use. With 

 some varieties which produce their roots in clusters around the "plant." 

 the labour of digging may be lessened by throwing a furrow away from 

 each side of the potatoes. Digging machines are in use in the United States, 

 where considerable areas are devoted to this crop. 



When digging, care should be taken not to bruise the roots; a bruised 

 potato rots easily, though a clean-cut one keeps well. 



Storing. 



No difficulty has been experienced in keeping small quantities in dry 

 sand. The tubers on being dug are allowed to dry in the sun for a few 

 hours, and are then placed away in sand, and keep through the winter 

 perfectly. 



