FEEDING THE HOP PLANT. 77 



Many other combinations of the ingredients men- 

 tioned on Page 76 may be made. But in any formula, 

 the object should be to supply the nitrogen, potash and 

 phosphoric acid in such forms that part of each element 

 shall be available for the plant in early spring, and 

 then from week to week, as growth advances, but not 

 force a growth when the plant is maturing its cones. 



The large proportion of nitrogen contained in hop 

 vines is wholly lost when they are burned, though the 

 mineral elements are retained in the ash. Since this 

 plant draws so heavily upon soil (or air) for this most 

 expensive element, certainly it should be retained so 

 far as practicable by plowing under the vines, provided 

 they are not infested with germs of disease so as to re- 

 quire burning. Spent hops are specially rich in nitro- 

 gen, and when they can be had for the hauling, should 

 be spread on the ground and cultivated under. 



A great number of other substances are much used 

 in England and on the continent, such as shoddy, waste, 

 woolen rags, fur waste, fish manure, and basic slag 

 from phosphoric acid. Irrigation may here be prac- 

 ticed, for it is essentially a feeding process. No matter 

 how much plant food is in the soil, unless there be suffi- 

 cient moisture, the crop cannot utilize it. Moreover, 

 the hop must have an abundant supply of water, be- 

 cause nearly nine-tenths of the vine's weight consists 

 of water. Frequent stirring of the top soil, or a mulch 

 of strawy manure, leaves, weeds, cornstalks, or any 

 such material, will carry a crop through a drouth that 

 would otherwise be fatal. Where irrigation is practiced 

 in California, the water is run through one furrow in 

 the middle of the rows, or one on each side. Sometimes 

 two or three such irrigations are enough, again more 

 may be necessary, while in a Colorado hop yard, the 

 water is turned on six to nine times. If the water sup- 

 ply is scant, a very little can be made to irrigate a large 

 number of plants by the device illustrated in Fig. 29. 



