400 



RESTING VEGETATION, 



and retarding may be greatly facilitated ; and the imitation Is easy when 

 plants are kept in pots. Ligneous plants may be thrown into a state of rest 

 by stripping them of their leaves, wlien the wood of the year is nearly ripe, 

 and at the same time shortening back the shoots to matured buds. Vines 

 against walls in the open air, when treated in this manner, come into leaf the 

 year afterwards somewhat earlier than vines in the same circumstances, but 

 not so treated : but when the practice of early pruning is continued every 

 year, the habit becomes fixed, and in a few years they will be found to break 

 earlier by ten days or a fortnight. Even pruning after the leaves drop in 

 autumn, as we have seen, has a tendency to produce an earlier development of 

 the buds than when that operation is deferred till spring ; because the num- 

 ber of buds to be nourished during winter being smaller, they are swelled to a 

 larger size (779), and the more ready to be developed. In general, whatever 

 tends to ripen the wood in ligneous plants, and mature the leaves in herbs, 

 tends to bring the plant into a state of repose ; and hence the value of walls, 

 dry borders, dry soils, and warm exposures. It may even be affirmed, that 

 with plants under glass the period of repose may be changed from what it is 

 in their native countries to what is most suitable for ours. Thus the natural 

 period of rest for plants which are natives of the Canaries is from April to 

 October, and of growth and maturation during our winter and early spring, 

 when we are most deficient in solar light ; but there can be little doubt that, 

 by the application for a series of years of a system of acceleration and retard- 

 ation, plants, natives of the Canaries, might be induced to flower during our 

 summers, and undergo their period of rest during our winters. We do not 

 say that the object would be worth attempting, but merely that we think it 

 is practicable. 



855. The advantages of putting trees that are to be forced into a state of 

 rest, and thus rendering them as excitable as possible previously to the appli- 

 cation of artificial heat, have been forcibly pointed out by Mr. Knight. The 

 period which any species or variety of fruit will require to attain maturity, 

 under any given degrees of temperature, and exposure to the influence of 

 light in the forcinghouse, will be regulated to a much greater extent than 

 is generally imagined, by the previous management and consequent state of 

 the tree, when that is first subjected to the operation of artificial heat. 

 Every gardener knows that when the previous season has been cold and 

 cloudy and wet, the wood of his fruit-trees remains immature, and weak 

 abortive blossoms only are produced. The advantages of having the wood 

 well ripened are perfectly well understood ; but those which maybe ob- 

 tained, whenever a very early crop of fruit is required, by ripening the wood 

 very early in the preceding summer, and putting the tree into a state of 

 repose as soon as possible after its wood has become perfectly mature, do not, 

 as far as my observation has extended, appear to be at all known to gar- 

 deners ; though every one, who has had in any degree the management of 

 vines in a hothouse, must have observed the diff'erent eff'ects of the same 

 degrees of temperature upon the same plant in October and February. In 

 the autumn, the plants have just sunk into their winter sleep ; in February, 

 they are refreshed and ready to awake again : and wherever it is intended 

 prematurely to excite their powers of life into action, the expediency of 

 putting these powers into a state of rest early in the preceding autumn 

 appears obvious. {Hort. Trans, vol. ii. p. 368.) Mr. Knight placed some 

 vines in pots in a forcinghouse, in the end of January, which ripened their 



