HOUSES FOR ALPINE PLANTS. 



165 



a season of beauty ; and not only by a frame, or frames, but also 

 by a simple cradle of ashes or of fibre, in which the "hardies" 

 maybe plunged when " off duty." 



The construction of Alpine houses is, or may be, of the 

 simplest. Its essential conditions are few. The first is an 

 amount of free air (" ventilation " is too weak a word) such as 

 perhaps no other class of plants exacts. The second is that the 

 plants shall be brought near the glass, and so not become 

 " drawn." This is best secured by giving the house a low- 

 pitched roof, and by avoiding side-lights. 



But while the ventilation must be unusually complete, there 

 should not be a draught, and the movable roof must be sound 

 enough not to allow of drip. In other respects the work 

 may be rough and inexpensive, though for choice of course it 

 should be good at all points. The roof must, in my judgment, be 

 removable, and that fact constitutes the only real peculiarity of 

 these structures. Such simple low houses as are occasionally 

 built for Auriculas will generally answer the purpose. 



The best mode of ventilation at seasons when the roof is in 

 place is by large wooden shutters beneath the staging on each 

 side ; and the roof should be made of movable lights, which may, 

 and should be, wholly removed in summer, late spring, and early 

 autumn. At other seasons they may, for additional ventilation, 

 be lifted, or drawn up or down at pleasure. Air should by all 

 these means be freely admitted night and day throughout the 

 year, unless it is unavoidably excluded in shutting out fog or 

 perhaps extreme frost. 



The small houses which I have made and used for some years 

 for the purpose answer all the foregoing conditions ; and as they 

 are both simple and cheap, I may as well describe them with a 

 little more particularity, though I shall suggest some improve- 

 ments as the result of my experience with them. 



They are, so to speak, " home-made," each consisting of ten 

 ordinary garden-lights, 6 feet by 4, five lights on each side, 

 giving a house 21 feet long by 10 feet broad. The rest is of wood, 

 and is put up by a local carpenter under direction. The cost of 

 each house is from £20 to £30. It is painted slate or stone 

 colour within, the darkest green without, and these, I think, are 

 the most suitable colours. The floor is only the natural soil, and 

 it and the staging are kept well watered daily in spring and sum- 



