6 Gardening Under Glass 



There is, however, this difference. Under 

 some conditions a qnite heavy clay soil will 

 give good results outside, whereas soil for inside 

 use should always contain enough decayed vege- 

 table matter (humus) and sand, so that it will 

 never pack and stay heavy and wet. Even if 

 such soil as you do have available happens to 

 be mostly clay, it can be changed and made 

 suitable for greenhouse use by following the 

 suggestions given in a later chapter. 



If, then, you have good, rich, mellow old gar- 

 den soil already at hand, you have the ground- 

 work for your glass gardening. If you have not, 

 such a soil may be made up quickly by the 

 methods suggested on pages 38 and 60. Or, for 

 immediate use, obtain a quantity of soil from 

 any near-by florist or market gardener. A few 

 bushels of soil will fill a good many pots ! 



Temperature, You know, no matter how 

 little gardening you have done outside, that no 

 plant will grow when it is very cold; that some 

 will grow in early spring or late fall, when it is 

 still "chilly," and that others will thrive only 

 during the warm weather of summer. 



Just so, in the glass garden, you will find that, 

 below a certain temperature, nothing will grow; 

 that in a cool temperature some things will 

 thrive; and that to succeed with yet others, 



