THE CANADIAN HORTICULTURIST 



Floral KdlLlon. 



A prize winning collection of vegetables shown by T. S. Purvis at the Calgary Horticultural 



Exhibition, 1914. 



The Beneficial Effects of Fall Cultivation 



John Gall, Inglewood, Ont. 



IT is generally recognized that fall 

 cultivation of soils has a beneficial 

 effect upon fertility. Let us con- 

 sider the subject from the point of view 

 of the requirements of crops. It will 

 make the central facts clearer, perhaps, 

 if we first of all consider the chief pro- 

 perties of a fertile soil. It is required 

 of a good soil that not only will it af- 

 ford a safe anchorage for the roots oi 

 plants, but that it must give, during 

 the growing season, a constant supply 

 of water to the transpiring foliage. 

 Furthermore, it must be able to yield 

 up to the feeding rootlets all those dif- 

 ferent mineral constituents, such a^ 

 phosphates and salts of potash, as well 

 as those simple compounds of nitrogen 

 that are absolutely required by all gar- 

 den crops. 



The capacity of the soil to hold air is 

 one of the most essential aids to fer- 

 tility. Ventilation is just as important 

 for soils as it is for ordinary dwellings, 

 as, in the absence of pure air, the ac- 

 tive, living roots of our ordinary culti- 

 vated plants would sicken and perish. 

 Moreover, as the oxygen of the air is 

 used up in the process of respiration,, 

 not only by the roots, but also by the 

 vast population of germs that inhabit 

 the soil, certain waste products of a 

 poisonous nature are produced, and 

 these must be removed or rendered 

 harmless if the soil is to be kept fit and 

 sustained at its highest point of effi- 

 ciency. Lastly, a fertile soil must be 

 able to take up the sun's heat and re- 

 tain it. "Warmth is of supreme import- 

 ance, and especially so in spring. If at 

 times the land is too wet, the heat is 



absorbed by the useless water, and the 

 soil remains cold and uncongenial to 

 early growth. 



Cultivation promotes these condi- 

 tions of soil fertility. The one great 

 mechanical effect of digging is that it 

 makes the soil finer in grain, and the 

 finer the grain the greater is its fer- 

 tility. To appreciate fully the import- 

 ance of this fact let me refer for a mo- 

 ment to the way the roots of a plant 

 feed. It is well known that all food 

 taken up from the soil must be ab- 

 sorbed in solution in w-ater. No solid 

 particle, however minute, can pass 

 through the membrane that acts as a 

 covering to the young roots and root- 

 hairs. But it is a peculiarity of all till- 

 age plants that their roots are slow to 

 take up what we may term "loose'' 

 water — that is, water that is free to 

 drain away from the soil. The water 

 they really take in is the water that 

 clings to the surface of each little damp 

 particle of soil, as such water is more 

 highly charged with food slowly dis- 

 solved out of the little solid mass to 

 which both the film of water and root- 

 hair are so closely attached. Ordinary 

 digging tends to break up the soil into 

 a finer mechanical condition, and so 

 tends to increase its water-holding 

 power. 



Fall cultivation carries the crum- 

 bling process much further, especially 

 in the case of heavy or stiff soils. By 

 throwing up the soil in rough ridges, 

 the frosts of winter, bv freezing (and 

 therefore expanding) the w^ater within 

 the pores of the soil, causes the coarse 

 lumps of soil to swell, and, because of 



this pushing apart of its particles, co- 

 hesion is weakened and their former 

 closeness of texture is destroyed. The 

 ridges quickly dry out in the March 

 winds, and are easily pulverized when 

 spring operations begin in the garden. 

 This expansive force of freezing water 

 is by far the most powerful agent at 

 the gardener's disposal for the breaking 

 down of lumpy soil and so far convert- 

 ing it into a mellow and kindly work- 

 able condition. Neglect of this rela- 

 tively clieap and easy method of in- 

 creasing fertility is a refusal to take 

 advantage of one of Nature 's most gen- 

 erous offers to aid the gardener in his 

 efforts to secure the best services of the 

 soil in the bountiful production of 

 crops. 



Cultivation and Fertility. 



A grower should always think in 

 terms of area of soil particles available 

 for exploitation by roots, rather than 

 in terms of superficial area of his gar- 

 den. A well-tilled plot of a rood area 

 may be quite as productive as a badly- 

 tilled plot of an acre, as it aU depends 

 upon the fineness of the soil. A little 

 hard cube of soil has six sides or sur- 

 faces. If it is broken in two, the six 

 sides become twelve, and if these two 

 are again divided, there will be twenty- 

 four sides, over each of which a water 

 film can cling, and so the work of dis- 

 solving out plant food substances from 

 the soil can be extended over four 

 times a greater area in the last-men- 

 tioned case than in the first. In fact, a 

 cubic foot of soil, such as is used for 

 potting purposes, represents in reality 

 about an acre of absorbing area for 

 roots. 



Almost all soils contain practically 

 an inexhaustible supply of plant food, 

 if only it could be made available. The 

 only natural way in which it can be so 

 made ready for the roots is through the 

 dissolving action of tightly - clinging 

 water films. It follows that working 

 the soil is equal in effect to manuring 

 it. Furthermore, such thorough culti- 

 vation, by increasing not only the 

 Avater-holding power of the soil, but 

 also its air-holding capacitj^, encour- 

 ages the growth and general activity of 

 useful bacteria in the soil, and espe- 

 cially such forms as are engaged in the 

 work of nitrification. 



Strawberry plants should be mulched 

 late in the fall to prevent any injury 

 from alternate freezing ami thawing 

 during the winter. 



Cut out all dead canes from the 

 raspberry- and blackberry plantations, 

 leaving only M-ood which grew' this 

 .rear. 



Grapes should be pruned and cov- 

 ered before the ground freezes. 



Delay miming fruit trees until 

 March or April. 



