614 



HORTICULTURE 



December 8, 1906 



Why are Flowers Double — and What For ? 



Doubtless this question has teen asked so far back 

 that the memory of man knowoth not. 



We are told and asked to believe that all flowers are 

 elaborated leaves. If so, the double flowers are more 

 elaborated than single ones, but — 



Are the stamens with the anthers filled with pollen 

 only elaborated leaves ? 



Are the pistils, ovaries, pericarps and embryo germs 

 only elaborated leaves? 



Whether double or single 



"Your voiceless lips O flowers are living preachers 

 Supplying to my fancy numerous teachers." 



Double flowers are admired and are great favorites; 

 whether they actually possess more beauty than single 

 ones depends entirely upon the views of the observer. 

 The structural change from single flowers to double ones 

 is said to be a transformation of stamens into petals. 

 This is more or less confirmed by the general absence of 

 normal stamens in double flowers and the frequency of 

 partially transformed petals to which are often attached 

 portions of stamens containing perfect pollen. 



It is held by some that intensive cultivation in rich 

 and highly elaborated nutritious soils will promote the 

 change from single to double and further that many 

 plants, with nature's assistance alone, never bear other 

 than single flowers but when subjected to high cultiva- 

 tion, produce double flowers, but if this be accepted how 

 shall we explain the one or more branches bearing 

 double blossoms on the hawthorn or the double blossoms 

 on the furze bush ? It cannot be either high living on 

 the one side or starvation on the other. 



Undoubtedly double flowers are developed from some 

 positive abnormal condition of the plant, or that part 

 of the plant on which they occur. If due to high cul- 

 tivation on one hand, or starvation on the other, double 

 flowers of any genus or species could be had at will. 



If it were in any manner possible to ascertain the 

 time and methods, if any, when and how the double 

 forms appeared of such narcissi as the double dafEodil 

 and the double phoenix, the double Gesneriana tulip, 

 the double hyacinth among bulbous plants, and the 

 double wall flower and double Eagged Robin, the double 

 flowering cherries, apples, peaches' and plums were first 

 brought to notice it would no doubt aid investigation. 

 Circumstantial evidence in my opinion is so strong that 

 I have no hesitancy in believing that the original plants 

 on which the first flowers appeared on the above men- 

 tioned species were not subjected to either cultivation 



or artificial treatment any more than were large num- 

 bers of their immediate neighbors, and own kindred 

 which bore single flowers only. It is reasonable to infer 

 and doubtless is true that when discovered they were 

 subjected to methodical propagation and cultivation 

 which has enabled them to occupy the positions they 

 now do. The methods of propagation of the cherries, 

 apples, peaches and other tree forms, is by budding and 

 grafting — which in the cherries has been carried on for 

 thousands of years — the propagation of the other men- 

 tioned plants has been offsets and divisions. 



Some species are more easily made to bear double 

 flowers by cross fertilization than others, a fact well 

 illustrated in the tuberous begonias from Bolivia and 

 Peru — not only have the species Boliviensis Veitchii, 

 Davisi and Pearcei bred and inbred with each other but 

 they have given the most marvellously double flowers in 

 any genera, and this so recently — 1857-65. Whether 

 Seden anticipated double flowers in his first crosses has 

 never been stated; possibly not; however, they stand 

 out boldly as representatives of what can be ac- 

 complished by intelligent pollenization and as a com- 

 pounding of species it has been perfectly done. There 

 is no doubt the species are not far removed from each 

 other, or the results would not have been so positive in 

 such a short time. This begonia family is an expansive, 

 erratic, amenable, controllable lot; however, some species 

 as Evansiana are intact as yet. What a parent this 

 would make crossed with some of the above hybrids ! 

 This and nitida are two of the oldest species. Tlie 

 begonias are comparatively recent to cultivation. 



The zonal section of pelargoniums is another family 

 wherein much doubling was done in a short time. I 

 remember in 1848 or '49 on the back wall of a con- 

 servatory a geranium 13 or 14 feet high with leaves 

 12 inches across and trusses of flowers two feet apart 

 with narrow petaled, ragged, semi-double scarlet flow- 

 ers. This came from Belgium and I recognized it just 

 before the advent of Gloire de Nancy as Marshal de 

 Champflour, which was one of the parents of Gloire de 

 Nancy. Jean Sisley and myself were about a tie in 

 getting a double white — mine was through Hendersoni 

 — since which time the numbers of double pelargoniums 

 have been legion. Whatever the family may be that 

 contains double flowers, there always will be a percent- 

 age of plants with flowers having perfect stamens and 

 stigmas according to their species— carnations, 15 per 

 cent., pelargoniums, 15 to 20; begonias, 7 to 20; dahlias, 

 30 to 70; fuchsias, 60; roses, 40 to 60, etc., so that 

 if the progeny were left to themselves the double flow- 



