370 GREENHOUSE MANAGEMENT. 



average weight. The following trial with French 

 Breakfast illustrates the above : 



The total number in each bed was 155, thus in the 

 sub-irrigated bed about one-half were fit for the market 

 at the first gathering, and four days later the remainder 

 were marketable, whereas in the surf ace- watered bed but 

 little more than one-fourth were ready on the 23d, and 

 three pullings instead of two had to be made, and the 

 average size was less. The market value of the sub-irri' 

 gated was more than double that of the others, even 

 though earliness is not taken into account. The chief 

 gain due to earlier maturity, however, is because of the 

 fact that the beds may be cleared several days sooner, 

 which is a matter worthy of consideration. 



Lettuce is a much more profitable crop than rad- 

 ishes, and some of the results with it have been quite 

 equal to the above. The following are some of the 

 results with the Grand Kapids, taken at random from 

 notes of recent experiments : 



Experiment No. 1. 



No plants. Weight. 



Sub-irrigated, 55 17 lbs. 8 oz. 



Surface irrigated, 55 9 lbs. 8 oz. 



Experiment No. 2. 



Sub-irrigated, 75 23 lbs. 15 oz. 



Surface irrigated, 75 18 lbs. 3 oz. 



Experiment No. 3. 



Sub-irrigated, 50 14 lbs. 12 oz. 



Surface irrigated, 50 9 lbs. 13 oz. 



Some cases can be given where other varieties have 



shown even better results, and a number in which the 



crop has been more than doubled, by sub-irrigation. 



Fifty per cent is considered a fair average gain, and 



