218 



Principles of Plant Culture. 



cutting is preferably cut shortly below a node, but this 

 is not essential in all plants. 



In this kind of propagation a mild bottom heat is 

 helpful; though it is sometimes carried on during the 

 summer months without artificial heat. 



382. Propagation by Leaf Cuttings. A considerable 

 number of plants, including the bryophyllum, begonia, 

 gesnera and others, readily develop growing points of 

 the stem and roots upon their leaves, a fact often 

 turned to account in propagating these plants. Well- 



PIG. 103. Leaf of begonia on surface of propagating bed, form- 

 ing young plants. (After Bailey.) 



matured leaves, with the principal nerves cut across on 

 the under side, are held in close contact with the sur- 

 face of the propagating bed by pegging or by light 

 weights, or the leaf may be cut into pieces, which may 

 be placed in the propagating bed and treated as ordi- 

 nary green cuttings (378). 



The leaves of the bryophyllum form rootlets and 

 buds from the notches on their borders wherever these 

 chance to come in contact with a moist medium. 



