THE VEGETABLE GARDEN 335 



fies the injurious effects of dry weather. It also results in breaking 

 many of the feeding roots between the rows. The frequent use of 

 the cultivator should be substituted as far as possible for hoeing. 

 If a severe frost is apprehended soon after the plants come up, the 

 tops should be covered by throwing a furrow to each row. 



Mulching. While mulching with hay, straw, leaves, or other 

 litter frequently increases the yield and is specially valuable in tid- 

 ing over a season of drought, it is not generally practicable on farms 

 where potatoes are grown on a large scale. Its place is in the garden 

 rather than in the field. It is a substitute for cultivation, and it is 

 generally cheaper to maintain a soil mulch by frequent cultivation 

 than to apply litter. If a mulch is employed, it can be applied over 

 the entire surface or in the furrow above the seed pieces, or between 

 the rows. Mulching in the furrow is not commended by the results 

 of tests in Colorado, Louisiana, and Michigan. In striving for a 

 large yield, with little regard to cost, or to insure against drought, 

 mulching is useful. 



Material intended to serve as a mulch should first be exposed to 

 the weather, so as to cause the sprouting of any seed it may contain. 

 It is better to apply a mulch after potato plants have made some 

 growth, as an earlier application may result in smothering some 

 plants and in injury from late frosts. 



Harvesting and Storing. The death of the vines is the signal 

 for digging the main crop. For the early market potato growers do 

 not wait for this, but are governed by the size of the tubers. As long 

 as any portion of the vine is green the tubers can continue to grow. 

 In gardens very early potatoes are sometimes obtained by carefully 

 removing a few of the larger tubers from the growing plant, re- 

 placing the soil and allowing the smaller potatoes to continue grow- 

 ing ("grabbing"). The large amount of labor required prohibits 

 "grabbing" except when early potatoes are selling at a price very 

 much higher than can be expected from the later crop. 



In harvesting a large area a high-priced potato digger is fre- 

 quently used; hand digging with a four-tined fork is probably the 

 best method on small areas, though many make use of a potato hoe 

 or of a plow. Careful handling always pays, and extreme careful- 

 ness is necessary, especially with the early crop, to prevent injury to 

 the tender skin of the immature potatoes. In harvesting, as well as 

 in storage, potatoes should be exposed to light as little as possible. 

 In storing potatoes a low temperature is required. The potato tuber 

 is uninjured by a temperature of 33 F., and one authority gives the 

 freezing temperature of potatoes 30.2 F. Warmth favors sprouting, 

 which injures potatoes both for planting and eating. 



Most of the farmers have potato houses or cellars constructed for 

 storing their stock and holding the unsold portion of the crop 

 through even the coldest weather until they can market it. Some 

 growers, especially those near town, depend on the warehouses of the 

 dealers alongside the railroad tracks. The common type of store- 

 house on the farm is a cellar walled up with concrete or stonework, 

 about 8 or 9 feet deep, with a low wooden roof above it, giving a con* 



