PREPARATION OF SOIL 85 



and therefore they require a much longer exposure previous 

 to the planting season. If the soil is a strong or heavy 

 loam it should be trenched or deeply dug in the autumn or 

 early in the winter, and have the surface left in a rough state 

 to enable the pulverising and purifying action of the winter 

 frosts and rains to have full play in the exercise of their 

 beneficial influence. Light soils may be trenched or dug 

 at the same time as those which are heavy, or they may be 

 prepared in the spring as may be found the most con- 

 venient. 



In trenching ground for Dahlias the soil should be 

 broken up to a depth of at least 2 feet, and if the 

 bottom spit consists of clay, gravel, or other unsuitable 

 material it should not be brought to the surface as in 

 ordinary trenching. The best means of avoiding this is 

 the adoption of the following course of procedure. First 

 open out a trench 2 feet wide and 12 inches deep, 

 and instead of taking out the bottom spit in the same 

 manner as in ordinary trenching dig it to a depth of 12 

 inches. This having been done, take out a second trench 

 in a manner similar to the first and put the soil into the 

 first trench, continuing this until the whole of the area has 

 been broken up to the desired depth. By this course of 

 procedure a deep root run is provided without burying the 

 well-worked soil beneath that which is not favourable to 

 rapid root development. 



The application of manure requires careful considera- 

 tion, for not only has the right kind to be selected, but it 

 should be applied at such time as will enable the plants to 

 obtain from it the fullest possible benefit. Manure from 

 the farmyard or stable is the most suitable for Dahlias, and 



