32 PLANTS FOR WINDOW GARDENING. 



and free from mould or dirt ; cleanliness is a point too much 

 neglected. 



In some sections of our country, much difficulty is expe- 

 rienced in growing heaths ; the water containing salts in 

 solution which are fatal to the plant, and we know nursery- 

 men who have altogether abandoned their culture. This 

 seems the case in limestone countries, and we have noticed 

 that heaths, of the tender varieties, when watered with 

 " hard " water, grew sickly and soon died. The best plan 

 is to use only rain water, and pursuing this course no diffi- 

 culty will be experienced. It is a curious fact, that in its 

 native countries, the heath is never found in a soil of which 

 the substratum is lime or chalk. In England, heaths are 

 always grown apart from other plants ; with us they occupy 

 the coolest part of the green-house. As a general rule, 

 nothing short of frost is too cold for them, and some 

 varieties will bear several degrees of frost without injury. 

 In the wild state, they are distributed over a vast range of 

 country, which accounts for the different temperatures the 

 varieties require ; the degree of cold adapted to each, must 

 be the lesson of experience. Among gardeners, heaths are 

 termed hard- wooded or soft- wooded ; the former make only 

 a chort growth each season, for example, E. Cavendishii; 



