424 THE PRINCIPLES OF FLORICULTURE 



mercial cut-flowers in summer. Considerable revenue 

 is derived in some localities by growing various annual 

 plants out of doors for summer sale. Among those easily 

 grown from seed are bachelor's buttons (Centaurea 

 Cyanus), snapdragons (Antirrhinum majus, and its 

 varieties nanum and grandiflorum) , asters, sweet peas, 

 ten-weeks'-stock and lupines. The propagation and 

 culture of annual plants not already discussed are similar. 

 Therefore, the cultivation of the aster is taken as a type. 



710. China asters, botanical classification. Order 

 Composite ; genus, Callistephus ; species, chinensis. 



711. China asters, botanical characters. A stout, 

 erect, leafy annual, two or three feet high, corymbosely 

 branched above. The stems are angular and of a purple- 

 brown color. The colors vary considerably, but are 

 mostly in shades of white, purple, pink and red. 



Habitat. The rocky hills of northern China. 



712. Commercial importance. The China aster is of 

 considerable commercial importance. It supplements 

 the carnation during the summer when cut-flowers of 

 many species are lacking. It has excellent keeping 

 qualities and lends itself well to general use. It is probably 

 more extensively grown for cut-flowers than is any other 

 garden species. 



713. Culture. Asters are not difficult to grow. They 

 are not particular as to the type of soil, but require a 

 liberal amount of thoroughly decomposed, organic matter.' 

 The early varieties do best on the lighter soils, but the 

 late varieties grow well on a heavy soil. The soil should 

 be thoroughly prepared, for asters are very particular in 

 regard to tillage. The soil in which they are to be placed 

 should be top-dressed in the fall and plowed. In the 

 spring the land should be plowed as early as possible and 



