162 REMARKS ON CULTURE OF ROSES IN POTS. 



compost, either by frequent shiftings or by placing them at once into 

 a considerable mass, the decomposition of the matters contained in it 

 will supply them with all the food requisite to a healthy and vigorous 

 development ; and it is only when the plants are sufficiently supplied 

 with light to elaborate the food taken up by the roots, that a consider- 

 able supply may be safely indulged in. It may form matter of ex- 

 periment whether animal, vegetable, or mineral manures are best 

 suited to the plants in question ; or whether a substance combining 

 each of these would possess still more fertilizing properties than 

 either of them in a separate state; liquid manure, consisting of the 

 drainings of dunghills, or formed from animal excrement or decayed 

 hotbed manure, has been proved to be very beneficial ; nitrate of soda 

 has also been strongly recommended, and may be best applied in a 

 liquid form ; in these cases (especially in the latter) the utmost cau- 

 tion is necessary not to use it too strong, as many plants have been 

 found to suffer severely by inattention to this important point. 

 These stimulating fluids should moreover be always used in a very 

 diluted state, and in this state they may be applied to strong and 

 vigorous plants once in two or three applications ; but to more deli- 

 cate ones, and to all at an earlier period of their existence, they must 

 be much more cautiously and very sparingly applied, and only at 

 considerable intervals. It cannot be too strongly insisted upon in the 

 culture of all plants under any circumstances, that if supplied with a 

 greater amount of food than is really necessary, not only will the 

 action of the manuring substances be impeded, but a positive injury 

 to the vital functions will be the result, just as the animal stomach 

 becomes disordered and impaired by being overloaded with food ; and 

 the richer the quality of this food, the more injurious will be that 

 result. Toplants in pots, this consideration is of infinite importance : 

 an excess of food applied to them has not an equal chance of draining 

 away or of being diffused in the surrounding medium, and conse- 

 quently the roots are forced into excesses which, under the increased 

 temperature and refracted light of a plant-house, lead to more than 

 ordinarily injurious results. 



The elucidation of the culture of these plants in pots involves a 

 consideration of climate ; and in this particular there is ample scope 

 for variation of treatment. It is no part of the present inquiry, as I 

 have already observed, to enter into what is regarded as the " forcing" 



