204 Commercial Gardening 



another, or the crops upon it. Whereas, if hot water is used, the pipes 

 and structures are fixtures in one particular spot, and cannot be interfered 

 with or moved from place to place with ease. And, again, to secure any- 

 thing like a reasonable minimum output on commercial lines, far more 

 glass would have to be used with hot-water apparatus than is necessary 

 under the true French system, where only manure, lights and frames, and 

 bell glasses are used. Perhaps these facts will appear more forcible from 

 a comparison between the material required to cultivate a 2-ac. French 

 garden and a similar area of ground under glass in the usual way. 



I. FRAMES AND BELL GLASSES (CLOCHES) FOR A TWO-ACRE FRENCH GARDEN. 



Square Square 

 yards. yards. 



900 lights (for 300 frames) = 1800 



20 per cent allowance for pathways ... = 360 = 2160 



3000 cloches = 600 



20 per cent allowance for pathways ... = 100 = 700 



Total space covered with glass ... ... =2860 



Total space uncovered but useful for other crops = 6820 



Area of 2 ac = 9680 



It will thus be seen that when every light and every cloche is in use, 

 and making an allowance for pathways, only 2860 sq. yd. or less than 

 one-third of the whole area is covered with glass, most of the remaining 

 two- thirds being available for other successional crops. And it must be 

 remembered that some of the ground which is open one season will be 

 covered with cloches and frames the next, so that a perfect rotation of 

 crops and a thorough sweetening and " sterilizing " of the soil by exposure 

 to the weather takes place in regular order. 



II. Two ACRES OF GROUND COVERED WITH GREENHOUSES. To cover 

 this space with modern greenhouses would take twelve houses, each 240 ft. 

 long and 30 ft. wide, each greenhouse covering 800 sq. yd., or about J ac. 

 The cost of twelve such houses would be not less than 4560, and probably 

 a good deal more, according to the quantity of piping used, and the kind 

 of boiler, to say nothing of the cost of coal and coke needed to maintain 

 the requisite warmth. 



The cost of the plant for a 2-ac. French garden would be approximately: 



300 frames and 900 lights 450 



3000 cloches at 5 per 100 150 



making a total of 600, or nearly 4000 less than the capital outlay for 

 covering 2 ac. with greenhouses. 



About 1000 mats would be necessary for a French garden at a cost 

 of about 70, but only about one-third of these would have to be replaced 

 after the first two or three years. 



Each year also about 800 tons of manure, at a cost of about 240, would 



