394 



THE GRAPE. 



Fig. 300. Span-roof Graptry. 



GRAPE HOUSES. It rarely occurs that the foreign varie- 

 ties are successfuly cultivated in the open air, and the pro- 

 tection of glass becomes necessary. The increased cer- 

 tainty of a crop, and the greatly improved flavor of the fruit, 

 can be hardly comprehended by those who have only seen 

 the more hardy foreign sorts ripened in open air. A house 

 without fire heat, is comparatively cheap, and managed 

 with moderate attention. 



Grape houses are of three kinds, the cold house, which only 

 protects from the exterior changes of the weather, and re- 

 tains the heat of the earth and of the sun ; the forcing 

 house, used for ripening early grapes by the assistance of 

 artificial heat ; and the late house, to be also heated artifi- 

 cially, to ripen, during winter, the later varieties. 



The best cold houses are made 

 with span-roofs, as in fig. 300; 

 while the lean-to house, fig. 301 ; 

 is best adapted to forcing, afford- 

 ing better security against the ad- 

 mission of cold. For this purpose 

 the latter should also have a dou- 

 ble wall at the back. To admit 

 the free passage of the roots un- 

 der the walls, the border being on 

 both sides, the posts should be 

 either stone or brick piers, set 

 deep enough in the ground to be 

 unaffected by frost, and the walls 

 built upon thick connecting slabs 

 of stone near the surface. Posts 

 3.1. Lean-to Grapery. of durable timber will last many 

 years, when the structure is built of wood. In the latter in- 

 stance, the back wall should be double-planked, and the space 

 between filled with closely rammed dry tan. The sashes 

 for the roof should be of two lengths, lapping slightly at the 

 middle, and sliding past each other in separate grooves. 



Border for the Vines. This should never be less than 12 

 feet wide, and if 20 or 25 feet, it would be better. The 

 roots of grape vines run rapidly to a great distance, and it 

 .'s indispensable to their successful growth to furnish ..hem 



