Missour1 Botanical 
Garden Bulletin 
Vol. VII St. Louis, Mo., April, 1919 No. 4 
THE DAHLIA 
The unusual display of dahlias at the Garden during the 
summer of 1918 was of such beauty and excellence as to 
arouse much enthusiasm and has helped to stimulate a re- 
vival of the use of this flower. Ordinarily, extremely hot 
weather is detrimental to the proper development of the 
dahlia, forcing it to remain practically inactive during the 
season, its thes beginning usually too late to produce any 
quantity of bloom before frost in the fall; but last summer 
proved that the St. Louis climate is not necessarily unfavor- 
able to these plants, and with proper care a fair measure of 
success may be expected except when prolonged periods of 
drought or heat occur. a 
The dahlia, with its great variety of forms and coloring, 
its dense masses of dark green foliage and brilliant flowers 
standing out in sharp relief, is a most useful plant for ob- 
taining striking yet harmonious effects. The flowers range 
from one-half inch in diameter to the size of a huge 
sunflower; in color from maroon which is almost black to 
a pure white, including many combinations of tints and 
shades, in brilliancy rivaling the salvia and in delicacy ap- 
proaching the orchid. 
The small single, red, purple, or yellow flower must have 
been known in Mexico, its native habitat, long before it 
was first described by Francisco Hernandez (1615). The 
next reference to the plant was made by Vitalis Mascondi, 
in 1657, and in 1787 it was first mentioned as a cultivated 
flower by de Menonville, a French botanist then in Mexico. 
Its introduction into Europe: was accomplished in 1789 
through Vincentes Cervantes, director of the Mexican 
Botanic Garden, who sent seeds to England, and to Abbe 
Cavanilles, director of the Royal Gardens at Madrid. Cavan- 
illes succeeded in raising plants which produced single and 
semi-double flowers. These he described in “Icones et 
- Descriptiones Plantarum” (1791), naming the genus 
“Dahlia” after a Swedish botanist, Andreas Dahl, and the 
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