220 Use of Charcoal in Pot Culture. 



in German gardens, to all cultivators ; for nothing is more con- 

 trary to the nature of those plants, than to set them in the open 

 greenhouse to make their first shoots, where they are conse- 

 quently in a dry situation. Most of them, when treated with a 

 gentle equable warmth, like that of a previously used dung bed, 

 will be much more fine than if placed in a higher and drier 

 temperature. Watering the tubers before they begin to grow is 

 very disadvantageous, and yet it would be absolutely necessary 

 if the pots stood in a greenhouse ; we prevent the evil by mak- 

 ing the earth in which the tubers are to be set sufficiently damp, 

 only slightly pressing them down, and immediately covering 

 them with earth in the dung bed. Only when the latter begins to 

 dry, it should be moistened all over with the watering-pot; and this 

 operation should be continued till all the tubers have made shoots, 

 and then each can be watered singl}^ With respect to preserving 

 them through the winter, I have to observe that these tubers, 

 as soon as they are taken in, should be placed in the greenhouse, 

 not too near the glass, and the earth covered with moss, by 

 which they will be prevented from drying up too soon, and the 

 necessity of moistening the earth obviated. By such treatment, 

 want of success in the cultivation of these splendid ornamental 

 plants can never be complained of. But to our subject. 



These tubers, plunged in the ashes, soon shot up vigorously. 

 As they ought to be grown in a high frame in summer, but which 

 could not be immediately prepared, they remained in this low 

 bed, which was only raised, dug up, and kept covered with 

 earth. They absorbed a great deal, and required watering every 

 day. When they were taken up, most of the roots, as may be sup- 

 posed, had grown over and under the pots; they had penetrated 

 into the charcoal, and grown so strong, that it was absolutely 

 necessary to replant the tubers in pots considerably larger 

 in size. I, of course, mixed charcoal with the earth in which 

 they were to be planted, in the proportion of rather more than 

 half. All the above-named species showed extraordinary luxu- 

 riance under this treatment; some were particularly rich in their 

 inflorescence, and the green of their leaves was much more 

 intense ; in others, the period of flowering was of unusually long 

 duration, so that while others planted in the usual soil had long 

 ceased flowering, these continued to vegetate freely. Very small 

 tubers, from which in the first year no flower was to be expected, 

 flowered very beautifully, as was the case with Gesnera atro- 

 sanguinea. The ^roideae, namely those with spotted leaves, 

 such as Calddium pictum, C. bicolor, C. discolor, C. splendens, 

 C. poe'cile, C. haematostigmum, C versicolor, &c., excited uni- 

 versal admiration. Several species of Billberg/a and Tillandsz'a, 

 to which I also added charcoal, soon exceeded in luxui'iance 

 those that were growing in common earth. From what was 



