THE NEW SYSTEM OF POTTING. 
109 
development of parts, in approximation to a condition of nature ; and the 
Restrictive or frequent shifting system, an application of materials proportionate to 
the existing vigour of the plant in its successive stages of growth. 
In alluding to the general features and ultimate effects which distinguish the 
Accumulative from other modes of cultivation, its relative value will be more 
readily inferred by showing its connexion with, and dependence upon, those prin- 
ciples of Horticulture which are calculated to ensure the most perfect development 
of vegetable growth. 
The only natural mode of perpetuating the constitutional vigour of a species 
is by reproduction from seed; and it is strictly in harmony with this law of 
Nature that the various modes of propagation and cultivation are to be viewed. 
Thence it follows, that in proportion as the means employed for the multiplication 
of plants are artificial in their character, will be the premature exhaustion of the 
individual parts thus multiplied ; in other words, if, in the propagation of a 
desirable plant by cuttings, the latter be taken from a specimen which is already 
partially exhausted by excessive development of its parts, or excess of bloom, 
the parts thus detached will partake of the impaired vigour of the parent. 
And, in continuation of the same principle, a plant which has been primarily 
derived from its parent stock as a layer, will possess less constitutional or vital 
energy than others derived from the same source as cuttings, in consequence of the 
former (the layer) already possessing, in its detached parts, a larger share of that 
maturity which approximates to an ultimate development of growth than the latter. 
The conclusions to be derived from the foregoing remarks are, that the several 
organs of a seed, a cutting, and a layer, are each endowed with a principle of 
vital energy varying in power from a seed downwards. 
It may further be stated, in relation to the present subject, that the vital 
functions of plants are diminished in force in proportion as the primary development 
of their parts is prematurely hardened or matured, whether arising from excess or 
deficiency of the elements which sustain them. 
Much that is superior in cultivation is known to depend upon the skilful 
application of materials modified to the variations of local influence and after- 
management. 
In support of a progressive and accumulative system of cultivation, the following 
principles may be offered, apart from those minor evidences which every successful 
routine of practice supplies. 
1st. " For the maintenance of a plant in health, it is indispensable that the 
supply of fluid by the roots should be continued and uninterrupted*." 
2d. " The smallest leaf at the extremity of a branch of a lofty tree must assist 
in setting in action the absorbing power of roots, at whatever distance those 
roots act from the other organs. If this reciprocal action is not maintained without 
* Lindley's Principles of Horticul. 32, 
