THE HORTICULTURAL SOCIETY OF NEW YORK 



' (c) Pompon type: Same as o or b, but flowers (heads) 

 must be under two inches in diameter. 



Cactus. — Double flowers. 



(a) True, fluted type: Corollas long, narrow, incurved or 



twisted, with sharp or fluted points and with the 

 margins revolute (rolled backward or outward), 

 forming in the outer florets a more or less perfect tube 

 for more than half the length of the corolla. 



(b) Hybrid cactus or semi-cactus type: Corollas short as 



compared with previous type, broad, flat, recurved or 

 twisted, margins only slightly revolute and tubes of 

 outer florets, if any, less than half the length of the 

 corolla. This type intergrades with the decorative 

 and paeony-flowered classes. 



The " cactus " class is one of comparatively modern develop- 

 ment and one that has done much to popularize the dahlia in 

 recent years. Its known history goes back less than five decades. 

 It is said that in 1872, a Dutch florist received from a friend in 

 Mexico a consignment of seeds and roots and that among the 

 mostly rotten roots was one that gave rise to a j^lant bearing a 

 scarlet or crimson flower roughly resembling a rather flat-rayed 

 specimen of a flower of the variety now cultivated under the name 

 of Standard Bearer. This new form had made its way to England 

 by 1879 and was there called the cactus dahlia on account of the 

 similarity of its flowers to those of a showy cultivated cactus, 

 Cereus spcciosissiiiius. Nothing like it now seems to be known 

 in a wild state in Mexico and its origin is shrouded in mystery. 

 It is lielieved that all of the hundreds of widely different varieties 

 of modern cactus dahlias have been derived, partly by the aid of 

 crossing with the older types, from this one strain in less than 

 fifty years — a most remarkable example of what nature's tendency 

 to variation can do in short time, when aided and encouraged 

 by .man. 



Soil, Fertilizer, Water, and Location 



In the matter of soil for growing dahlias successfully, it has 

 been found by experience that a light loam, with good drainage, 

 is the most favorable. A soil that is good for corn is usually 

 good for dahlias. A light sandy soil will do as well as any, if 

 one can supply sufficient fertilizer and moisture. A very rich 



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