. Cassell's popular gardening. Gardening. Fig-. 51.—Experimeut to sliow tlie Downward Ten- deucy ol: Growth in Eoots even when innmiuated from below. the monster roots. I\Iere bulk, then, without growth is of no practical advantage. The necessary conditions for growth have already been mentioned in general terms under the head of Gernrination. (See ante, Vol. I., p. 23.) AYith a sufficient knowledge of general principles the culti- vator can readily adjust his practice to pai-ticular plants, and to his own particular requirements. It may. however, not be in- ==p==ap^_ appropriate to allude to
. Cassell's popular gardening. Gardening. Fig-. 51.—Experimeut to sliow tlie Downward Ten- deucy ol: Growth in Eoots even when innmiuated from below. the monster roots. I\Iere bulk, then, without growth is of no practical advantage. The necessary conditions for growth have already been mentioned in general terms under the head of Gernrination. (See ante, Vol. I., p. 23.) AYith a sufficient knowledge of general principles the culti- vator can readily adjust his practice to pai-ticular plants, and to his own particular requirements. It may. however, not be in- ==p==ap^_ appropriate to allude to cer- tain phenomena of growth which it is especially neces- sary to bear in mind. Continuous or In- termittent Growth. — Strictly speaking, growth, at least in the higher plants, is never absolutely con- tinuous, it is always aiTested at times to be resumed at another period. But bear- ing this qualification in mind it is easy to see that, by maintaining uniformity of conditions, we induce more or less continuous gro\vi;h. In forcing operations, w here the heat is regularly kept above a certain temperature, we have an illustration of this. But even here it is the practice to lower the temperature at night and to raise it in the day. At night, though the tempera- ture may not be deficient, the light is absent, and it is consequently good practice to lessen the teniperatm-e so as to secure a more even balance of conditions. Even in the tropics the night temperature, we must remember, is invariably lower than the day temperature. Day and Night Growth.—Strange as it may seem at first sight, there is no doubt that growth is arrested in the day-time imder the exposm-e to light —not absolutely, but certainly relatively. The energy of growth is decidedly greater at night than in the day. Dming the day, when the leaves are exposed to the action of the sun, food or food-mate- rials are absorbed or transformed in the manner already alluded to. The greater energy is devoted dui'ing
Size: 2102px × 1189px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade18, booksubjectgardening, bookyear1884
