60 



CROPS UNDER GLASS 



Mr. Work : The florists men cannot see the beds in a prac- 

 tical way. The vegetable men cannot see the raised benches. 

 What we have been trying to do here is to see whether there 

 are points from one side that would be helpful to the other. 

 There is the question of bottom heat. Bottom heat is regard- 

 ed as useful to others. We have undertaken to find out about 

 that. In the far end of our greenhouse in the old range, there 

 is a bed under which there are four steam pipes eighteen 

 inches apart. We let just a little heat circulate there, so that 

 we keep the soil just ten degrees warmer than the air. We 

 want you to go out and see this. We understand there are 

 some growers in Illinois who have bottom heat under their 

 ground beds and who get good results with it. I do not know 

 the details of their plan and do not know how successful it is. 

 Have any of you any ideas on that? Does your lettuce grow 

 more quickly on the benches, Mr. Kilboum? 



Mr. Kilbourn : I think it would the forepart of the year 

 anyway. 



Mr. Wrigley: All of our lettuce we grow in ground beds 

 I have tried it on beds in the air, but they grow too spindly. 

 You cannot hold them back, and you have to water so much 

 with beds in the air, that it seems to cause mildew. On ground 

 beds we always find hold the moisture a great deal better. 



Mr. Hunter: I have one house in which the two side 

 benches are on beds, and the center is the solid bed. I like 

 the solid bed best. I have about every three feet a row of tile. 

 I can grow a crop with this. There is a circulation of air 

 underneath. They are about ten inches under the soil. 



Mr. Work: Do you use them for watering? 



Mr. Hunter: No. 



Mr. Work: Could you? 



Mr. Hunter: I think I could. 



Mr. Work: What is your soil? 



Mr. Hunter: These pipes come right to the top of the 

 subsoil, over the gravel. 



