PROPAGATION OF PLANTS. 69 



is not only rarely necessary, but it leads undoubtedly to 

 many cases of failure; not that the cutting at or below a 

 joint either hinders or assists the formation of roots, but 

 from the fact that, when a slip is cut at a joint, the shoot 

 often has become too hard at that point, while half an 

 inch higher up, or above the joint, the proper condition 

 will be found. I know that it will root even when in 

 the too hard condition, but the roots emitted will be hard 

 and slender, and, as a consequence, will not be likely to 

 make a plant of the same vigor as that made from the 

 cutting in the proper state; besides, as the hard cutting 

 takes a longer time to root, its chances of failing from 

 unfavorable atmospheric conditions are thus increased. 



With these instructions for the proper state of the cut- 

 ting, I now proceed to describe the medium wherein 

 it is to be placed, and the conditions of temperature, 

 moisture, etc. If these are strictly followed, failure is an 

 impossibility ; for the laws governing the rooting of a 

 slip are as certain as those governing the germination of 

 a seed. In our own practice, when these conditions are 

 strictly followed, failure is unknown, when the cutting or 

 slip is in the proper condition of health. 



The best degree of temperature to root cuttings of the 

 great majority of green-house and bedding plants is 65 

 of bottom heat, indicated by a thermometer plunged 

 in the sand of the bench, and an atmospheric temperature 

 of 15 less. A range of 10 may be allowed, that is, 5 

 lower or 5 higher; but the nearer the heat of the sand 

 can be kept to 65, and that of the rest of the house to 

 50, the more perfect the success will be. If a much 

 higher temperature be maintained, it will be at the 

 expense of the ultimate health of the plants. These 

 temperatures refer to propagation under glass from 

 November to April Of course, when the outside tern- 



