Forcing Houses for Carnations 



the size of glass used in carnation structures has gradually been advanced 

 from 8 in. x 10 in., or 8 in. x 12 in., to glass uniformly 16 in. wide and from 

 16 in. to 24 in. in length, preference being given the 16 in. x 24 in. size, of 

 double-thick glass. 



At the present time the general consensus of opinion is that the even- 

 span house, ranging from 28 ft. to 30 ft. in width, built with the ridge run- 

 ning east and west, with ample ventilation at the ridge, sides and ends, is 

 as near the ideal type of carnation forcing house as can be attained. These 

 houses are always glazed with double-thick glass, 16 in. wide; the height 

 of the ridge from the floor being from 12 ft. to 14 ft., and of the eaves 5 ft. 

 Two lines of ventilation, opening on either side at the ridge, are provided. 

 With some growers, especially those whose greenhouses are located in shel- 

 tered localities, where the summer temperature rises high, continuous lines 

 of ventilation are provided under the eaves, upon both sides of the house, also 

 upon the ends. This is very desirable where houses are planted as early 

 as July or August, or where the planting is done in the spring and the 

 plants grown in the houses throughout the summer. When the ventilators 

 upon the sides and ends are thrown wide open, and those at the roof are 

 also raised to the fullest extent, a much lower temperature can be main- 

 tained than in houses where the ventilators at the sides and ends are 

 absent. 



A further reduction in temperature may be secured by liberally watering 

 the walks and the ground underneath the benches, as evaporation of mois- 

 ture will have a tendency to cool the atmosphere. In some instances, the 

 writer has been able to maintain a temperature of two degrees lower under 

 glass than the thermometer registered in the shade outside. This result 

 may be more readily attained if the glass is shaded, or striped with a solu- 

 tion of white lead, as described in Chapter IX. 



The importance of ample ventilation must not be lost sight of; never- 

 theless, many successful growers, and especially those whose houses are 

 located close by the sea shore, within reach of the salt fogs, as well as those 

 whose locations are upon high altitudes, where their structures are exposed 

 to strong breezes, do not find side ventilation necessary ; in fact, claim 

 that it is a detriment. But at Queens we have found it decidedly bene- 

 ficial and desirable. 



Aspect of Forcing Houses 



All forcing houses should be located in such a position as will expose 

 the plants contained therein fully to the rays of the sun during the day- 



