﻿Aprjl,i 9 c4.] THE ORCHID REVIEW. 99 



"After experimenting in various ways with water containing nitrate of 

 soda and ammonium sulphate, we could see that there were good results 

 derived, but the need was ever felt of a formula that was based on the exact 

 needs of the plants— one that would eliminate the element of uncertainty as 

 to strength of solution. 



" It was at this stage that Cookson published his formula in the 

 Orchid Review, and he stated that by its employment on plants separated 

 by its use merely — otherwise on the same bench — he could easily pick out 

 the ones his gardener had applied it to, and in the light of our experience 

 this is easily believed. 



" The formula Cookson recommends is : three ounces of nitrate of 

 potassium, two ounces of ammonium phosphate by weight, dissolved in 

 three gallons of water, then one liquid ounce is used of this solution to each 

 gallon of water applied to the plants. — E. O. Orpet, in address before the 

 Horticultural Society of New York." 



It is quite clear that something was wrong. I should suspect too much 

 water ; and perhaps the leaf-mould was not of the right kind. But the 

 writer goes into the matter deeply, and gets right down to the reason of 

 things. He speaks of cultivators having yet to be weaned from the 

 pervading idea that the roots of Orchids take up food for their sustenance 

 from the potting medium, like other terrestrial plants. But thousands of 

 Orchids are terrestrial plants, and they certainly obtain their food in the 

 same way. Then he speaks of the indestiuctibility of Osmunda fibre, hence 

 the food supply was insufficient, and he was forced to the conclusion that 

 tens of thousands of Orchids were being " literally starved to death "; yet he 

 adds "soil will nor feed them." Now it strikes me that both fallen leaves 

 and Osmunda fibre come under the head of decaying vegetable matter, 

 though one decays and gives up the food supply too fast and the other not 

 fast enough, so that the happy medium might be found by combining the 

 two in the right proportions. However, Mr. Orpet seems to have found 

 salvation in the use of the " Cookson formula" combined with indestructible 

 Osmunda fibre, though he almost suggests that the latter might be replaced 

 by some such material as asbestos, with equally good results. The one 

 point that is clear to me after a perusal of the article is that the " compost " 

 must be of the right mechanical composition, and that it must contain the 

 necessary food. How the food is to be got there is a matter of secondary 

 importance. It is well known that, in a wild state, epiphytic Orchids 

 derive a great part of their food supply from decaying vegetable matter, in 

 which decaying leaves form no inconsiderable item. If cultivators can find 

 an efficient substitute, well and good ; but in cases of failure it is not so much 

 ^the fault of the leaves as of the method of using them. One may have too 



