76 GARDEN PLANNING 



This ensures good drainage. At least two 

 feet of soil should be put above the drainage 

 layer. The cost and trouble may be more^ 

 but the results will repay the gardener. 



Fig. 12. — Drainage for beds and borders 



Borders prepared in this way do not suffer 

 from water-logging even during wet winters. 

 In hot summer weather they neither bake nor 

 become dry for any great distance down. If 

 the trenching is done in the autumn, the winter 

 frosts will help to break up the clay lumps, 

 reducing them to a consistency more nearly 

 approaching loam. The important point in 

 the treatment of clay land is to secure a suffi- 

 cient admixture of loose porous material to 

 destroy the tenacity of the clay and to permit 

 of moisture freely finding its way down through 

 the mass of soil. A certain proportion of 

 vegetable matter is a gain, as it has manurial 

 value. Hence the gardener may cast into his 



