GSE OF CHARCOAL AS A MEDIUM FOR PLANT GROWTH. 473 



THE USE OF CHARCOAL AS A MEDIUM FOR PLANT 



GROWTH. 



By A. Appleyard, M.Sc, Rothamsted Experimental Station. 



The writer has recently had occasion to look up the references to 

 the use of charcoal as a medium for plant growth, and it is thought 

 that a short account of this subject may be interesting and lead to 

 further work. 



Many experiments with charcoal must have been made by gardeners 

 during the nineteenth century which unfortunately have not been 

 recorded in garden literature. In this way much valuable in- 

 formation has been lost. It is not until 1841 that we find many 

 references to the use of charcoal by gardeners. At this time the 

 editor of the Gardeners' Chronicle, speaking of its use, says : * " Very 

 little is at present known about it in this country. It is said to be 

 the means of making the most difficult kinds of plants strike root 

 readily from cuttings. Gloxinias and plants of that description 

 are made to flower freely, to remain a long time in flower, and at 

 the same time the colours are rendered more deep and brilHant." A 

 little later we read that Pansies which have been planted and struck 

 in charcoal have a very vivid colour, and that Comhretum pur- 

 pureum, a plant not easily increased, is speedily rooted in charcoal, f 



An apparatus J for propagating plants, invented by Professor 

 Martius, of Munich, was described in the Gardeners' Magazine in 

 June 1841. It consisted of a vessel packed with charcoal, in which 

 the seeds were placed. A pit was dug, and a tank of water heated 

 by a flue was fixed in it. The charcoal was then placed over the vessel 

 containing water. Most astonishing results are said to have been 

 obtained by this means, and indeed after a very short time we read 

 that charcoal " has gained a reputation which nothing now can 

 shake," and that the opinion of practical men is setting steadily in 

 its favour. 



During the 'forties charcoal was often used by gardeners, and 

 the garden literature of this time contains many references to 

 its use. It was found that orchidaceous plants grew well on charred 

 wooden blocks. The practice had also at this time been introduced 

 at Chatsworth, and further we read that nothing was more striking 

 than its good effects in the garden of the Horticultural Society. In 

 1843 the importance of the use of charcoal as a manure threatened 

 to revolutionize two-thirds of the practices then existing of gardening, 



* Gardeners' Chronicle, 1841, p. 537. 

 f Hovey's Magazine of Horticulture. 

 % Garten Zeitung, 1841. 



VOL. XL. 2 K 



