Jamnry 27, 1863. ] JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 



69 



Taking another class of plants occupying a glass structure, we 

 nave also very wide dissimilarity of climates to reconcile in an 

 artificial abode. The gales, might we not call them hurricanes ? 

 ■which move the plants almost to uprooting them, that occupy 

 the crests of a mountain region like the Cape of Good Hope and 

 elsewhere, differ so widely from the more calm abode of plants 

 occupying the flat plains of Australia, and elsewhere, that we 

 need not wonder at a Cape Heath being affected with mildew 

 when subjected to the dull murky air of a closely-pent-up house ; 

 while in the latter, such plants as occupy the temperate region 

 exempt from storm, and, probably, like the Calceolaria and 

 Chinese Primrose growing under trees, are more at home here 

 than when subjected to strong currents of air. That there are 

 many intermediate classes of plants is superfluous to admit, and 

 it is from the numbers of them and from other sources that 

 our general treatment of the whole ought to be guided. Let us 

 see how this has been done, or rather let us see in what way the 

 best results are likely to ensue, having reference to the other 

 conditions necessary to be observed at the same time. 



If we take an ordinary lean-to house in summer time, we shall 

 see that if it faces the south, the amount of heat it receives from 

 the bright glare of sunshine is immense ; and if no outlet be 

 made for the escape of this heat, it will speedily increase beyond 

 the endurance of the plants inside. 



An ordinary frame or pit, with the glass and woodwork fitting 

 closely, speedily becomes heated to an inordinate degree, and 

 many a batch of Cucumbers have fallen victims to not receiving 

 fresh air in time ; large houses, where the volume of air enclosed 

 is large in proportion to the heating surface, become heated less 

 quickly, and, consequently, the plants within them suffer less ; 

 so that close attendance on the air necessary for frames is an 

 important part of the duties of the gardener in charge. Thus 

 the amateur must bear this in mind, and not be led to think 

 that a small object requires little attention, for in the matter of 

 frames or pits, and houses, the former suffer most if not attended 

 to in time. The practical man knows this full well, and he often 

 takes a sort of half-and-half precaution, by leaving at all times a 

 little opening, not sufficient to meet the wants of a bright sunny 

 day, but enough to provide against a little bright weather that 

 may occur in his temporary absence. 



To reduce the proper time of giving and taking away air from 

 a number of glass structures devoted to different purposes, to 

 anything like a regular tabular form or scale, is to attempt to 

 revert to the practice of our grandfathers, whose adherence to 

 the figures of the thermometer has been long since set aside. 

 So many local and other conditions also militate against this, 

 that we cannot give even general instructions on the matter with- 

 out allowing for the many exceptions that are likely to arise, not 

 the least being the different aspects of the structure requiring ah', 

 the plants cultivated therein, as well as the time of year, and, 

 in fact, many other considerations of a similar character. Thus, 

 a lean-to house, or a frame, facing the south-east, will require 

 air to be admitted long before a similar structure that faces the 

 south-west will want it. So, also, the proper time for shutting-up 

 the one will be long before that of the other. 



Some other conditions also must be considered, and some 

 classes of houses require less air to be given them than others. 

 A span-roofed house, with the gable facing the 60uth heats much 

 less quickly than a lean-to ; while amongst the latter a Grape- 

 house, with the roof well covered with foliage, is much slower 

 in becoming hot than one less covered. The condition of the 

 external air must, in a great measure, determine the time and 

 circumstance of giving air, and the character of the heating 

 apparatus has also its full share of influence ; for, be it remem- 

 bered, that in general the greatest number of plants in a growing 

 condition benefit most by plentiful admissions of external air, 

 tempered, in some measure, before coming in contact with them, 

 but that such admissions are at the expense of the heating 

 apparatus. It is, therefore, with a view to save the latter, that 

 most houses requiring artificial heat are shut-up early in the 

 afternoon, in order to shut-in as large an amount of sun heat as 

 possible. The heat shut-in may often be from 20° to 30° more 

 than the minimum night temperature. 



Many other considerations often have to be attended to, the 

 expense of fuel being a great inducement to shut-in as mueh sun 

 heat as the plants will bear ; and, in the caBe of frame plants not 

 receiving heat from other than the fermenting material of the bed, 

 it is advisable to shut-up early in order to save all the heat. Cover- 

 ing the glass over soon after with mats on an extremely frosty after- 

 noon will, in a measure, prevent the escape of mueh of the heat. 



Houses, where there is a scarcity of coal or other heatin" 

 material, may be treated in like manner ; the character of the 

 outward air and the appearance of the evening determining 

 what is best to be done. I may, however, say that in very 

 severe weather, there is no harm in almost all houses being 

 allowed to fall from 5' to 8° lower than what at other times is 

 regarded as their standard. 



Greenhouse plants will take no particular harm at 36°, nor 

 those of the stove at 50°, while in milder weather they may 

 be 10° higher. 



I only point out these facts to the inexperienced, but they 

 must not take any further liberties until they have learned by 

 experience how much plants will bear. 



I may say, in conclusion, that the garden structure requiring 

 the least amount of fresh air to be given, is the cutting-frame or 

 propagating-house ; a close confined atmosphere favouring the 

 formation of new roots. A Fern-house also requires little air, 

 and so does one devoted to the growth of Orchids ; while 

 Pines, Cucumbers, and Melons, being tropical fruits, require 

 much less than those from the temperate regions of the earth ; 

 but the time, and mode of giving air, the quantity, and many 

 other particulars are too much for the present communication, 

 so I must defer noticing them until another opportunity. 



J. Robson. 



HOETICULTUKAL SHOWS IN THE NORTH 

 OF IRELAND. 



At page 25 of The Journal of Horticulture, " A Prac- 

 tical Gardener" communicates some strictures on horticul- 

 tural shows in the north of Ireland. Lest some of your readers 

 should form a bad opinion of us here, I trouble you with the 

 following remarks. 



He says he was desirous of advancing the interests of horti- 

 culture in his own immediate neighbourhood, but was dis- 

 qualified from attending one show from the fact of his employer 

 not being an annual subscriber to the Society, and blames the 

 Committee, some of them gentlemen's gardeners, for it. 



In the north of Ireland, gardeners are not recognised at the 

 shows to the same extent as in England. The plants are not 

 entered in their names, neither do their names appear promi- 

 nently in the award cards. The societies are kept up by annual 

 subscriptions, and, to insure an interest being taken in the 

 exhibitions, none but subscribers are qualified to compete. 

 Surely "A Practical Gardener" can find no fault with this, 

 as it is calculated to promote the interests of local horticul- 

 ture, the only object local societies aim at. 



Speaking of another Society, he objects because he was not 

 permitted to carry off more than one prize in each class. Every 

 one at all acquainted with horticultural societies is aware of the 

 universality of a rule to this effect. He is dissatisfied also, 

 because the second best dishes or collections were awarded 

 second prize, "no matter how inferior." This was not the 

 fault of the Committee but of the Judges, who, in all cases, are 

 authorised to withhold prizes should the subjects not be of 

 sufficient merit. But, it fortunately happened on this occasion, 

 the Judges were of a more liberal mind than " A Practical 

 Gardener," and did award the prizes, as an inducement to 

 further care and attention on the part of the gardeners. 



With regard to the last part of his communication. On one 

 occasion, in the north of Ireland, a rule was enforced that all 

 prize fruit was to become the property of the Society, but money 

 prizes more than treble the value of the fruit were offered as 

 inducements to competitors. The fruit was retained for a 

 special purpose, which was publicly known, and surely there 

 was no compulsion in the matter. "A Practical Gardener" 

 might or might not have competed just as he pleased. This 

 happened some time Bince, and was the only occasion on which 

 such a rule was carried out for the last twenty-five years. — - 

 Htbernicus. 



Mistletoe on the Oak. — Having read in one of your late 

 Numbers an article on the Mistletoe, in which you speak of its 

 being rarely found on the Oak, and do not name any placo 

 where it is still to be 3een, I write to tell you that there is a fair- 

 sized plant of it growing on an Oak on the land of H. Howard, 

 Esq., Thornbury Castle, near Bristol, and which has been there 

 for several years — marvellously eluding the ruthless hand of 

 Christmas decorators. — Constant Reader. 



