122 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



Sphagnum only, and with it I have been remarkably successful. 

 But by this method the roots grow so freely that it is necessary 

 to use very large pans for the plants, and this is often incon- 

 venient. I now find the same results can be obtained with 

 smaller pots, using a mixture of Sphagnum and fibrous peat or 

 turf. The one important condition — sine qua non — is to expose 

 the plants to the full sun and to water the soil abundantly. I 

 always thought that in the damp climate of England this method 

 of cultivation would not succeed, but I am glad to hear that in the 

 southern counties experiments have been made with good results. 

 In Geneva I never could persuade Soldanellas, Arnica montana, 

 Gentiana bavarica, G. purpurea, Saxifraga carpathica, S. 

 iberidifolia, &c, to flower until I planted them in Sphagnum ; 

 and a great many other plants are now beginning to succeed 

 very well with me by means of this system. 



But what you want in England is not at all the same thing. 

 Would that we could give you some of our sun-rays and a little 

 of our dry atmosphere ! One of the most difficult things for 

 you is the cultivation of the true rock-plants like Campanula 

 Zoysii, excisa, Elatinc, Eainerii, Edraianthi ; Senecio incanus, 

 leucophyllus, and uniflorus; Phytcuma comosum, humile; Andro- 

 sace ciliata, cylindrica, helvetica, Packer i, Wulfeniana,pubescens } 

 imbricata, Haussmannii, Heeri, Charpcntieri ; Draba tomentosa, 

 Saxifraga diapensioides, Eritrichium nanu?n, &c, which succeed 

 more easily in Geneva. Our English friends write to us very 

 often that these plants make them despair ; that they rot even 

 under the best conditions, &c, &c. I always give them the same 

 advice : Place your plants in an old stone wall or between the 

 crevices of your rockery in the full sunlight, and in a perpen- 

 dicular position, so that the tuft of the plant is parallel to and 

 flat upon the wall, the central axis being horizontal to it. Under 

 this system I have always obtained the best results. But of far 

 greater value than my own opinion is that of Edmond Boissier, 

 who covered his walls with the rarest and most delicate of Alpine 

 and rock plants, and my contention is that this is the only 

 method for keeping such delicate plants in good health in 

 England. It is not at all necessary to put any soil in the 

 crevices and holes made in the stone wall ; they should be very 

 narrow, so that the roots of the plants are pressed by the stones 

 as in their natural state. They find in the moisture of the stones 



