204: 



ON MANURING FOR HOPS. 



It is evident, from the foregoing* table, tliat thongli cwt, 

 of giiano are amply suiKcient to supply the acre ot hops with 

 its phosphates, yet that it requires 7 cwt. to supply the 

 potash. Consequently the 5 cwt. of guano might have 

 been replaced by a cheaper maniu'e destitute of phosphates, 

 but containing ISg lb. of potash. 



Hitherto I have spoken as if the hops, leaves, and bine 

 of the acre of Farnhams were of the usual or average 

 weight. But this was not the case. Owing to the un- 

 kindly weather, the yield was very deficient. It is no un- 

 common thing in some districts to grow a ton of hops an 

 acre. We will suppose a farmer to grow a ton of hops per 

 acre,' and that the mineral ingredients of the hop are in the 

 same proportion as in those which were analyzed. 



We will suppose that the bine and leaves were double in 

 quantit}'^, but containing the same per cent, of inorganic 

 matter as the others. This would give us 64 lb, removed 

 per acre by the golding hop, while the grape hop would re- 

 move about 75 lb. per ton, though perhaps 64 lb. might be 

 taken as the average. 



The following- table will then show us the weight of guano, 

 wheat straw, or farm-yard dung, per acre, necessary to be 

 put on the land, to replace the potash withdrawn by the 

 hops, bine, and leaves : — 



Qiiantity of guano, wheat straw, or farm-yard dvng, an- 

 nnally necessary to replace the 64 Ih. of potash taheii 

 Jrom an acre of land, by a ton of hops, with bine and 

 leaves corresponding. 



Now, as the whole of the above methods of furnishing the 

 necessary amount of potash are enormously expensive, we 

 are necessitated to look to other and cheaper sources for this 

 valuable substance. 



Sevei'al salts of potash are well known in commerce, and 

 likewise to the agricultiu'ist. Nitrate of potash, or salt- 

 petre, is one, and common pearlash is another. 



