88 THE NURSERY-MANUAL 



be regularly planted. In outdoor practice, the cuttings which 

 are of medium length, from 6 to 8 inches, derive more bottom 

 heat than the very long ones, such as were formerly used for 

 the propagation of the grape. 



In indoor work, bottom heat is obtained 

 by means of fermenting manure, or, prefer- 

 ably, by greenhouse pipes. Cutting-benches 

 should have abundant piping beneath, and 

 in the case of many tropical and subtropical 

 species the bottom heat may be intensified 

 FIG. 89. Forsyth's by inclosing the benches below, so that no 

 cutting-pot. heat can escape mto t he wa ]ks. Doors 



may be placed in the partition alongside the walk, to serve as 

 ventilators if the heat should become too intense. 



Placing and protecting the cuttings 



Cuttings usually "strike" better when they touch the side 

 of the pot than when they are wholly surrounded by earth. 

 This is probably because the earthenware insures greater 

 uniformity in drainage than the earth, and supplies air and a 

 mild bottom heat ; and it is possible that the deflection of the 

 plant-food towards the side of the pot, because of evaporation 

 therefrom, induces better growth at that point. 



Various devices are employed for the purpose of securing 

 these advantages to the best effect. These are usually double 

 pots, in one of which water is placed. A good method is that 

 represented in Fig. 89, which shows a pot, b, plugged with 

 plaster of Paris at the bottom, placed inside a larger one. The 

 earth is placed between the two, drainage material occupying 

 the bottom, a, and fine soil the top, c. Water stands in the 

 inner pot as high as the dotted line, and feeds uniformly into 

 the surrounding soil. The positions of the water and soil are 

 frequently reversed, but in that case there is less space avail- 



