GREENHOUSES 89 



worked out by engineers and is to be had for the ask- 

 ing from any firm of greenhouse builders. 



The arrangement of beds and walks is a matter 

 of prime importance and should be planned before 

 the construction of the house is begun. Care should 

 be taken that the least possible amount of waste 

 space occurs and that the widths of beds and walks, 

 together with their location, are such as to facilitate 

 the work of management in the best manner pos- 

 sible. Usually a minimum width for a vegetable 

 house permitting of economical arrangement of beds 

 and walks is 30 feet. The width may be increased 

 if desired, but should rarely ever be less than this 

 distance. 



Beds may be either raised or solid. The raised 

 beds are simply benches raised from two to three 

 feet above the ground level and carrying from four 

 to six inches of soil, in which the crops are grown. 

 The heating pipes are usually carried underneath 

 the beds. The solid beds are in most common use 

 in the vegetable houses. They may be built either 

 with or without sides, maintaining the natural 

 ground levels or being raised from 12 to 18 inches 

 above it. If the soils are of the proper texture they are 

 simply improved by the additions of manures and 

 commercial fertilizers. When they are not desir- 

 able in any respect the surface layers are removed 

 and the desired composts placed in the beds. Solid 

 beds are much more easily controlled and generally 

 give much better success, especially in the hands 

 of the novice: It is not uncommon in many 

 of the larger houses to have them so arranged 

 that the manure may be hauled in and spread 

 directly over the beds from the wagons and the soil 

 plowed and prepared just as is done under out-of- 



