286 



JOITKNAL OF HORTICULTURE AND COTTAGE GARDENER. 



[ October 13, 1S03. 



tition in trade, the gardenere of this country are more than 

 ever enabled to apply with the greatest exactness the de- 

 grees of atmospheric heat and moisture required by plants 

 from more fovom-ed climates than that of this country. The 

 days of thin glass and ricketty old flues are fast being 

 numbered with the past, and more than ever are we enabled 

 in most instances to excel the open-air productions of 

 summer lands. It must not, however, be overlooked that 

 the means which have been called into operation to enable 

 us to supply with the greatest steadiness the two elements 

 referred to, are attended with evDs which require mitigation. 

 The almost air-tight manner in which hothouses are now 

 being constructed is productive of the deleterious influences 

 of a close and impm-e atmosphere; and a pure and con- 

 stantly renewed atmosphere is considered of so much im- 

 portance, that means are now being put in operation by 

 which, in the most severe weather of winter, a constant 

 change is effected without the dangers and evils previously 

 consequent on the admission of large volumes of frosty aii' 

 for only a short period of the day. Ajipliances of this kind 

 have now arrived at so advanced a condition, that it can 

 only be by the agitation of many years and the friction of 

 many minds that any fiu-ther steps of importance can be 

 looked for. We are apt to think so, at least, and are ready 

 to ask. What more can be done ? Can we not press into our 

 service fresh aids to cultivation, wliich shall be grounded on 

 demonstrated and self-evident principles ? To what extent 

 have we pressed into our service the knowledge which has 

 been placed within om- reach by our Liebigs and Johnstons ? 

 Or can it be said that the scientific research of such men 

 has simply explained to us the effects produced by the toil- 

 ing pains of merely practical men ? Be this as it may, it 

 is undoubtedly a fact that the practical application of the 

 discoveries of scientific men generally proceeds with cautious 

 steps ; and we have much to thank those bold and ciu-ious 

 spirits for, who are generally less benefited by theii- experi- 

 ments than are the community at large. A generation 

 produces few men like Knight and Mechi ; and however 

 such men may have benefited the art of cultivation, they 

 are^ generally laughed at by no small portion of theii- self- 

 satisfied compeers. 



It is to be feared that gardeners are very apt to look into 

 the reseai-ches of scientific men, and store some of the 

 more striking facts which have been demonstrated without 

 once attempting to reduce them to practice ; and, strange 

 to say, dabblers in matters of science ai-e ever associated 

 in many minds with crack-brained experimentalists, incom- 

 petency, and unsuccessful practice, just as if the possession 

 of correct knowledge and the successful application of it 

 were antagonistic — an idea which we fancy would be hard to 

 prove by any species of reasoning. No one can possibly 

 regret that the march of horticultiu-al appliances has enabled 

 ns to free ourselves to a gi-eat extent of the labour and filth 

 of the cumbrous dung-lining system. On the other hand, it 

 certainly is a question whether we have not left behind us 

 some of the redeeming points of that old and obsolete 

 system of forcing. 



Many of i!s well remember how vigorous and healthy many 

 plants used to grow in M'Phail-pits heated with dung 

 and leaves, and how many a sickly plant when placed in 

 dung heat regained that hue of health which nothing else 

 would impart. The almost sere and yellow leaf would 

 become green and fuU of substance under the influence of 

 the carbonic acid and ammonia evolved in the fermentation 

 and decomposition of stable-manure, and with which no 

 modern appU^.nces of heat are naturally accompanied. It 

 would be endless to refer to the many plants which thrive 

 better, and are more free fi-om insects under the influence of 

 dung heat, than that supijlied by either flues or pipes. 

 Many gai-deners to this day who grow Gardenias, and even 

 one or two other stove plants which are very subject to moalv 

 bug in the common stove, yet find that in dung heat they 

 are comparatively free from the pest. It has even been 

 asserted tliat subjecting Pines which are infested with white 

 scale to the steam of dung-linings, will rid them of so 

 desper.atc an enemy. 



It is a well-demonstrated fact that carbonic acid and 

 arnmonia form the chief food of plants, and these two con- 

 stituents are freely given off during the progress of the de- 

 composition of dung-beds, and this is what accounts for the 



vigorous growth and dark gi-een appearance which dung- 

 frames invariably impart to plants. This is the deficiency 

 which is attached to the use of modern heating appliances ; 

 and sm-ely it cannot be beyond the powers of the gardener's 

 resources to charge the air in glass houses with one or both 

 of these gases, so that the plants, largely capable as they 

 are of imbibing nourishment from the air, can appropriate 

 and assimilate them. Are we to conclude that an atmo- 

 sphere resembUng that produced by fermenting dung and 

 leaves cannot be attained when heat is obtained from hot- 

 water pipes ? Far from answering such a question positively, 

 it is at the same time questioned if ever such has been sys- 

 tematically attempted. 



In potting plants we have spared no pains nor attention 

 in feeding them thi-ough their roots v^-ith all the proper 

 elements of nourishment. Natural circumstances are imi- 

 tated to the best of our knowledge, and as far as artificial 

 cii-cumstances wiU permit. But all the while we are, it is 

 to be feai-ed, practically forgetting that the stems and leaves 

 of a plant are no more in a natural condition in a very small 

 amoimt of tightly-enclosed air than are the roots when 

 cramped up into a pot. The plant is removed from the 

 breezy air of heaven, and packed up into a glass bandbox, 

 and is too often left for long and weary hours closely shut 

 up, to rob the au- of its scanty supply of food, and to charge 

 it with gases injurious to itself. This is something like 

 suffocation and stai-vation combined, and is followed, as a 

 consequence, by the more apparent and no less desperate 

 ev-d of insects, which are rai-ely developed in the ammonia- 

 and-cai-bon-charged ah- of a dung-pit. Red spider and white 

 bug revel in the one case, while in the other they are far 

 less likely to make their appearance at all, and when they 

 do they never become so formidable and destructive. 



If these inferences be correct, it is surely time to inquire 

 whether there ai-e no means within our reach of producing 

 an atmosphere in our forcing-houses more akin to that pro- 

 duced by fermenting dung and leaves without having re- 

 course to the cumbrous and untidy presence of a heap of 

 those materials. That this would be desh-able in the forcing 

 of the great majority of our plants and fruits 'ivill scarcely 

 be questioned. There may be differences of opinion as to 

 how best to make such applications, but their beneficial 

 results have been of late very strongly impressed on my mind 

 by various results. In the early part of summer it was re- 

 solved to plant a house, which had fonnerly been a Peach- 

 house, with Vines. The house is a very old one, having 

 been erected about ninety years ago, and has, consequently, 

 many snug retreats for insects, and red spider in particular. 

 The Vines were struck from eyes in spring, and planted- 

 out when not more than a foot high. Fora time they pro- 

 gressed favoui-ably; but red spider, which has been a iearful 

 pest out and in-doors here this year, soon attacked them, 

 and in a very short time brought the young plants to a 

 complete stand-stUl. The popular remedies were applied. 

 The Vines were syringed, the hot-water pipes were rubbed 

 with siUphur, and fumes raised enough to choke one, but the 

 enemy was as active and destructive as ever. Ail hope of 

 getting the Vines to the top of the house this ye.ar was given 

 up. Their points were in some cases black and leafless from 

 the effects of the spider and the syringe together. I then 

 heard of an amatem- who had invariably been much troubled 

 with red spider, but who had escaped it this season, whUe 

 his neighbours were being sadly annoyed with it. He attri- 

 buted his success to the regular application of ammonia to 

 the atmosphere of the vinery. I then mixed up a small pot- 

 ful of Peruvian guano, and applied it regularly to the pipes 

 of the vinery, and so strongly was the air charged with am- 

 monia from the guano that it affected the eyes on entering 

 the house. This was regularly continued, and in less than 

 three weeks the Vines had changed to a dark green, began 

 to grow vigorously, and not a red spider could be found in 

 the house. The Vines soon found their way to the top of 

 the house, except a few which had been too severely punished 

 by the spider ever to make free gi-owth afterwards. The 

 change from a pale hue to that of a dark green in the case 

 of these Vines was next to magical. 



In oirr Pine-pits here guano has been regularly applied to 

 an extent sufficient to make the atmosphere smell strongly 

 of it, and all who are in the habit of seeing oiu' Pines ai'e 

 struck with their almost black appearance and their vigorous 



