GREENHOUSE PLANTS. 



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GREENHOUSE PLANTS. 



two or three feet in width ; and next 

 there is a path two or three feet in 

 width ; the remainder of the floor, 

 from the edge of the path to the back 

 wall, being occupied with a series of 

 shelves, rising one above another like 

 the steps of a staircase, on which the 

 pots of plants are to be placed. These 

 shelves may be nine inches or a foot 

 in width, and the height of one above 

 another may also be nine inches or 

 one foot. The mode in which arti- 

 ficial heat is communicated to such a 

 house is by smoke flues, or hot water 

 pipes. The fire should be at one end, 

 or behind the house, whichever may 

 be most convenient ; and the principal 

 flue or hot-water pipe should be along 

 the front wall, under the shelf ; or, 

 in some cases, it may be under the 

 path. The reason for this position of 

 the flue or pipe is, that heat always 

 ascends ; and, consequently, if the 

 source of heat were placed under the 

 back of the house, the heat would 

 ascend directly to the roof at the 

 upper angle of the house, and would 

 scarcely heat the lower or front part 

 at all. In order to admit of ventila- 

 tion, the front sashes should open out- 

 wards, or slide along a groove ; and 

 the roof sashes should also open by 

 sliding the one over the other. Other 

 minor details need not be here entered 

 into, as they are perfectly understood 

 by all constructors of greenhouses, 

 whether of wood or iron. With re- 

 spect to these two materials, iron ad- 

 mits of the greatest variety of shape, 

 such as a curvilinear ground plan and 

 roof, and it also admits most light ; 

 but the construction in wood is most 

 generally understood, and is rather the 

 cheapest. Very excellent and orna- 

 mental greenhouses in iron are 

 constructed by Messrs. Cottam and 

 Hallen, and wooden houses may be 

 made by any carpenter or joiner. 



Greenhouse Plants are those 

 which will not bear the cold of a 



British winter in the open air, but 

 that only require to be protected from 

 frost. Many persons injure their 

 greenhouse plants by giving them too 

 much heat in winter, and too little 

 air in summer, and are then sur- 

 prised to find their plants die, or at 

 least become sickly, and remain with- 

 out flowering, notwithstanding all the 

 care that has been bestowed upon 

 them. No greenhouse ought to be 

 kept at a greater heat at night than 

 from 35° to 40° during winter; but 

 the thermometer ought never to be 

 suffered to fall below 35°. In the 

 day, particularly if there be sunshine, 

 it will of course rise higher ; but the 

 fire should be lessened accordingly, as 

 the thermometer, even in sunshine, 

 should not rise in winter above 50°, 

 or at most 52° or 53°. A higher 

 temperature will induce premature 

 vegetation ; and the plant will waste 

 its strength in an abortive attempt to 

 produce flowers and seeds at a season 

 Avhen its nature requires it to be kept 

 in a state of complete repose. The 

 second fault, of giving too little air, 

 is an equally serious one. Plants can 

 no more live without fresh air than 

 without water; and even in winter, 

 the sashes of a greenhouse should be 

 opened for an hour or two, say from 

 twelve till two, in the middle of the 

 day, whenever the sun shines, or the 

 frost is not too intense. In the sum- 

 mer, say from the middle of May to 

 the middle of September, the plants 

 should be set out in the open air ; the 

 space on which they are to stand being 

 covered two or three inches deep with 

 small coal or slack, or ashes, to pre- 

 vent the worms from creeping out of 

 the ground into the holes at the 

 bottom of the pots. In cold and damp 

 seasons, the time for putting out the 

 plants may be delayed till June ; and 

 previous to their removal, the sashes 

 of the greenhouse should be left open 

 for a week or ten days, night and 



