HOT-HOUSE OR STOVE PLANTS. 



303 



From these most valuable results, which have 

 l^een compiled from the " Memoranda Sheet " of Sir 

 J. B. Lawes, we see that with both the varieties of 

 Potato experimented upon, just in proportion as the 

 character of the manurial supply was of a more sti- 

 mulating nature, so the crop increased in total bulk, 

 and the diseased tubers increased in quantity, while 

 the weight of small or " pig " Potatoes remained 

 nearly the same under all the different conditions of 

 manuring. Thus, without manure of any kind, the 

 total crop of " Pocks dug was 53 cwts. per acre, and 

 the weight of diseased tubers was 2| cwts. Whilst 

 under what may considered as the most complete and 

 stimulating manure — namely, a mixture comprising 

 potash, soda, magnesia, superphosphate, and nitrate 

 of sodium — the total crop obtained in the avei-age of 

 four years was 145| cwts. per acre, and the quantity 

 of diseased tubers in this crop was 18| cwts. per acre.. 

 Or, putting the facts in other words, for each 100 lbs. 

 of Potatoes grown without manure 5-2 lbs. were 



diseased, and for each 100 lbs. grown by the applica- 

 tion of the complex manure, 12-8 lbs. were diseased. 



Again, with the "Champion" variety, the total 

 crop harvested was, without manure, in the average 

 of the three years, 33^ cwts. per acre, and of these 

 ^ cwt. or 28 lbs. were diseased ; whilst with the combi- 

 nation of mixed mineral manure and nitrate of sodium, 

 164|- cwts. of Potatoes were obtained, and the quan- 

 tity of diseased tubers was 9 cwts. With this variety, 

 which is seen to be on the Rothamsted soil much 

 more disease-proof than the "Rock," for each 100 lbs. 

 grown without manure O'? lb. was diseased, "and with 

 the complex manure, for each 100 lbs. of Potatoes 

 produced o-o lbs. went bad in the ground previous to 

 lifting, or 7*3 per cent, less diseased tubers than with 

 the " Rock" varietj''. 



The following table shows some average results of 

 experiments conducted in America with Onions, 

 Potatoes, and Turnips, when grown under the in- 

 fluence of different manures. 



From the Report of the Connecticut Board or Agriculture tor 1880. 



Average Froduce per Acre vn Bushels. 





Onions. - 



-1 Year, 



Potatoes. 



—3 Years, 



Turnips.- 



-2 Years. 



Manures per Acre. 



Bulbs, 



Increase 

 over Un- 

 manured. 



Tubers, 



Increase 

 over Un- 

 manured. 



Bulbs. 



Increase 

 over Un- 

 manured. 



Nitrate of Sodium, 200 lbs 



Dissolved Bone-black, 300 lbs 



Miiriate of Potash, 200 lbs 



Nitrate of Sodium, 150 lbs,, and Dissolved") 



Bone-black, 300 lbs j 



Nitrate of Sodium, 150 lbs., and Muriate of ) 



Potash, 200 lbs f 



290 

 390 

 £30 

 510 

 680 



620 



500 

 400 



100 

 240 

 220 

 390 



330 



210 

 110 



79 

 127 



89 

 105 

 104 



117 



96 

 90 



48 

 10 



26 

 25 



38 



17 

 11 



205 

 ^40 

 425 

 417 



388 



477 



454 

 412 



235 

 220 

 212 

 183 



272 



249 



207 



These experiments are stated to have been made 

 mostly on what would be considered a poor, worn- 

 out soil ; and the general conclusions to be drawn 

 from them appear to be that a moderate dressing of 

 nitrate of sodium combined with superphosphate 

 (dissolved bone-black) is equally efficacious, whether 

 employed for Onions, Potatoes, or Turnips ; and in 

 the case of Onions and Turnips, these manurial in- 

 gredients are superior to stable manure, although it 

 is probable that the carbon of the dung had not had 

 time to operate during the short period over which 

 these experiments extend. Soluble and active ma- 

 nures produce their principal effect at once, being of 

 little benefit to subsequent crops. Sparingly soluble 

 manures, and those that must undergo decomposition 

 in the soil before their conversion into plant-food, 

 will continue to produce an effect over many years. 



71 



HOT-HOUSE OR STOVE PLANTS. 



By William Httgh Gower. 



Dalechampia. — These plants belong to the 

 Spurgewort family. There are, however, few species 

 sufficiently handsome to secure them a place in our 

 plant -stoves. They are plants of easy culture, 

 thriving best in a mixture of loam, leaf-mould, and 

 peat, in about equal parts, adding suffieient sand to 

 make the whole feel gritty when mixed. They enjoy 

 a strong heat and a liberal supply of water. The 

 flowers of D. Roezlii are a rich deep rose in colour. 

 There is a variety alha, in which the involucres are 

 white. In I), inadagoscareusis the leaves arc tri- 

 foliate, and the pair of leafy involucres which sur- 

 round the flowers are greenish-yellow. Spiing and 

 early summer. 



