140 THE FLORIST. 



ON DEEP CULTIVATION. 



Were we to examine the depth to which the roots of many of our cul- 

 tivated plants will penetrate a loose open soil in quest of food, we should 

 be less sceptical as to the advantages which deep cultivation affords to 

 the roots of plants. The market gardeners around London trench ofien 

 and deeply, not only to change the surface, as some suppose, but to 

 allow the roots of their crops to range as deep as they please, and with- 

 out this assistance the enormous crops of first-rate produce they obtain 

 from the land could not be obtained. If deep cultivation is requisite in 

 the rich and deep alluvial soils of the Thames valley, how much more 

 so is it on poor and shallow soils, which afford comparatively only a 

 limited pasturage for the roots of plants. 



It is true, gravelly and rocky subsoils are almost beyond the reach 

 of improvement; as the expense of breaking up the substratum would, 

 in most instances, be too great to pay. But this is not always the 

 case, for I have seen the brashy subsoil of some localities broken up 

 with good results, as well as some gravelly subsoils, particularly where 

 the layers of gravel are thin and mixed with clay or ferruginous matter, 

 rendering them impervious to water, as well as to the roots of plants. 

 By breaking through this crust, so as to admit a free passage for the 

 water, a marked improvement follows. Clay subsoils, however reten- 

 tive, are capable of being reclaimed ; but this is a work of time, as all 

 you can do, after thorough drainage, is to break up the clayey bottom 

 to the depth of twelve or eighteen inches, according to its nature, each 

 time the ground is dug or trenched. This bottom, when forked up, 

 should be kept as open as possible, which will facilitate the passage of water 

 through it, and the salts and ammonia carried down by the rains from 

 the manuring, &c,, of the upper soil will in time reduce its tenacity, 

 assisted by the decomposing action of the air, which will now have 

 better access to it ; and in a kw years, by practising this, you will find 

 your land gradually increasing in depth and productivtness. Many 

 calcareous and slaty rocks are likewise capable of improvement when 

 broken up and exposed to the action of the weather, and when shallow 

 soils rest on these descriptions of rocks, by all means, break up a 

 stratum of it yearly, below the top soil. Many hard compact marls of the 

 red sandstone and lias formations are as unfavourable for the growth of 

 plants as rock or gravel, and yet when broken up and exposed to atmo- 

 spheric influences, they make fertile soils capable of producing every 

 kind of crop. I remember some fifteen or sixteen years back paying a 

 visit to the garden of the late E. Davis, Esq., of Bath, whom many of 

 your readers will recollect was the first amateur Dahlia grower of that 

 day, and his plants were growing apparently in a mass of stones. The 

 garden of this gentleman was situated on the side of one of the oolitic 

 ranges which surround Bath, with barely a covering of soil over the 

 rock; this Mr. Davis had broken up two feet in depth, and had mixed 

 with it the surface soil and a little manure ; the luxuriance of his Dahlias 

 and general garden produce was remarkable, and may perhaps be 

 remembered by those of your readers who visited Entre-hill at the 

 time in question. 



