ACCLIMATISING OF PLANTS. 717 



and sends forth leaves ; it must be also able to produce flowers and 

 seeds, and to elaborate the peculiar secretions and products on which 

 its qualities depend. The seeds of Indian Hemp have been sent to 

 this country, and the plant has grown well, even to the height of ten 

 feet, with thick stems, vigorous leaves, and abundance of flowers ; but 

 they do not produce the churrus, a resinous matter which renders the 

 plant valuable in India as a medicinal agent. Summer heat is 

 wanting to enable the plant to perform all its functions. Such is also 

 the case with Ehubarb, which, as regards the size and vigour of the 

 plant, thrives in the climate of Britain, but the root does not produce 

 a medicinal agent of the same quality as that grown in Chinese 

 Tartary. 



Something may be done by the art of the gardener to render half- 

 hardy species of plants less tender. In this climate the great risk in 

 such cases is frequently not so much the degree of cold, as the accession 

 of it at the time when the plants cannot resist it, in consequence of 

 being fuU of sap. Attention, therefore, should be paid to bringing 

 the plants into as dry a state as possible at the beginning of winter. 

 Lindley remarks that the only means of effecting this consists in 

 thoroughly drained soU and an elevated situation — the first preventiug 

 a plant from filling itself with moisture during winter or overgrowing 

 itself in summer, so as to enable it to ripen its wood ; and the latter 

 securiog it from the action of those early frosts in autumn, or those 

 late frosts in spring, which are so pernicious even to our own wild 

 trees. In an elevated situation, a plant also escapes the risk of being 

 stimulated into growth by a few days' warmth, succeeded by nipping 

 colds, which so often occurs in our variable climate. 



