CULTURAL DIRECTIONS. 



145 



Exception to this rule should be made in favour of structures intended for 

 the cultivation of Filmy Ferns — Todeas, Trichomanes, and Hymenophyllums — 

 all of which thrive best when grown in a house with a north aspect and 

 subdued light. The exotic Fernery should also be a little below the level of 

 the ground : this disposition will ensure uniformity of temperature and per- 

 manency of moisture, both conditions most beneficial, but very difficult to 

 obtain in houses built above ground, especially when, as is generally the 

 case, these structures are supplied with shelves and open stages. Where a 

 naturally shaded spot cannot conveniently be found in which to erect the Fernery, 

 shading is at times indispensable, but it should only be afforded with a view 

 to preventing the scorching of the fronds, by breaking the rays of the sun, 

 and not to keeping out all natural light. In this case it is preferable to 

 shade by means of movable blinds, made of coarse canvas or of other suit- 

 able material, which should be of a nature sufficiently open to admit plenty 

 of light. The blinds should be let down for a few hours, according to the 

 situation of the Fernery, when the sun is strong, but should be drawn up 

 again as soon as there is no danger of burning ; for it is unwise to weaken 

 the substance of the fronds by subjecting the plants to the influence of per- 

 manent artificial shade. Although most Ferns are naturally adverse to strong 

 light, it is now acknowledged that, in the construction of a Fernery, the use 

 of ground or plate glass for roof glazing should be avoided. Numerous 

 experiments have been tried with the object of dispensing with shading when 

 ground glass had been selected as the best means of producing an even and 

 diffuse light, but its use in most cases, if not in all, has had to be abandoned. 

 The shading of the Fernery by blinds may, however, be successfully obviated 

 by the use of green-tinted glass, as in the Fern-houses in Kew Gardens, 

 where, in spite of all that has been said and written to the contrary, it 

 gives perfect satisfaction. 



The foregoing remarks apply exclusively to the external parts of the 

 Fernery. The organisation of the internal parts is a matter of no less import- 

 ance, and to give the subject as fair a share of attention as it really deserves 

 it is proposed here to divide the particulars into two sections. It is there- 

 fore necessary to deal first with the Fernery as it is understood by nurserymen 

 and market growers, as also by gardeners and others requiring Ferns to be 

 grown either for sale or for the sake of supplying decorative plants for the 



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