i08 maine agricultural experiment station. 



Summary. 



Constant watchfulness and the exercise of good judgment 

 are of more importance than adherence to set rules. 



A single house standing alone, covering 2,000 square feet of 

 surface, will require about twenty-five tons of coal for the year. 



One good man with' occasional help should be able to do all 

 the work in houses covering 4,000 square feet of ground sur- 

 face. 



The simplest form of glass structure is the cold frame. Aside 

 from its use in .starting early plants it is little used in "winter 

 gardening." 



The hot-bed is similar to a cold frame with the addition of 

 "bottom heat." 



The uneven span house is the form in most common use. 

 The even-span is used mainly for narrow propagating houses 

 and for conservatories. 



The best green house wall is that which, at least expense, is 

 perfectly rigid, is durable, and will effectually shut out drafts 

 of cold air. A cheap and effective wall is made by the use of 

 posts and matched boards. 



The glass for greenhouse roofs should be second quality, 

 double thick and of good size — 14x22 or 16x24 inches preferred. 



The object of ventilation is to purify the atmosphere, rather 

 than to lower the temperature. 



In modern greenhouse heating we have only to consider two 

 general systems — steam and hot water in closed circuits. 



In general, solid beds are advocated for plants requiring no 

 bottom heat, such as cauliflower, lettuce, radishes, etc.; while 

 for semi-tropical plants like melons, beans and tomatoes, 

 benches are preferred. 



When and how to apply water is more important than the 

 source of supply. 



There is a marked difference in the ability of plants to stand 

 direct sunlight. 



The secret of success is to have something on the ground 

 constantly. The most important crops are lettuce, tomatoes, 

 cucumbers and radishes. Asparagus, bean, parsley, etc., are 

 valuable for keeping up a succession of crops. 



