116 Svhtropical Vegetable-Gardening 



they may be fastened by nailing a light strip from one to 

 the other. The upper edges of the boards should be 

 pressed together firmly, but not hard enough to bruise the 

 leaves. The boards may be staked down on each side, 

 upright at first and slanted in later. In two or three weeks 

 the celery will be blanched suflBciently for use. 



Among other methods of blanching are those of putting 

 drain tiles around the plants, and of wrapping them with 

 thick paper, or covering with a paper tube; but all of 

 these have failed to meet the wants of celery-growers. 



Late in the season, or when celery has attained its full 

 growth, it takes nearly twice as long to blanch. This 

 should be borne in mind when celery is to be prepared for a 

 fixed date. (See lower figure, Plate VI.) 



Irrigation of celery. 



In following celery culture, it may be necessary to resort 

 to irrigation, for the water supply. This supply may be 

 distributed in one of three ways, — either by open ditches 

 at short intervals, by running tiles below the surface (sub- 

 irrigation), or by an over-head spray. 



When the water is distributed by open ditches, they are 

 cut 3 to 4 feet apart. In watering, these are allowed to 

 flow full until the earth is thoroughly soaked, then the 

 water is turned into another set, and this is continued until 

 the whole area has been treated. These ditches are shal- 

 low, only a few inches deep. On a clayey soil, they are 

 run nearly on the level ; but on sandy loam, there must 

 be a considerable decline in order that the water may 

 reach the further end. It requires a fall of 1 to 3 inches to 

 100 feet to make water run well on dry sandy soil. 



