PLANTING PERSIMMONS 



Japanese Variety Requires Pollinizers Under Most Conditions — Few Satis- 

 factory Pollinizers yet found — Native Persimmon Can Not be Used, 

 Because of its Incompatibility. 



H. Harold Hume, 



Glen Saint Mary, Florida. 



E\"ER since Diospyros Kaki 

 (commonly called the Japanese 

 persimmon) was introduced and 

 established in America about 

 1875, it has been noted in many 

 sections that though the trees produce 

 enough flowers to give good crops of 

 fruit, the young fruits or ovaries of 

 many varieties begin to drop shortly 

 after the flowers open, and continue to 

 drop, until, when the harvest season 

 arrives, no fruit remains to be gathered, 

 or so little that the planter is often 

 disgusted with their behavior. In some 

 seasons good crops are produced under 

 conditions quite identical with those 

 which prevailed in seasons when no 

 crop was produced. The cause of this 

 unf ruitfulness and this sporadic fruitful- 

 ness remained very much of a mystery 

 for many years. Naturally the culti- 

 vation of D. Kaki is not regarded 

 favorably by many who have attempted 

 it. 



As is usual in such cases, many theories 

 have been advanced to account for its 

 non-fruiting. Some said that the 

 trouble was due to too much cultiva- 

 tion, and that a system of weed or sod 

 cultivation would correct it. Others 

 said it was due to lack of potash in the 

 fertilizer and that heavy applications of 

 potash would correct the trouble. Still 

 others said that the growth and devel- 

 opment of the calyces forced the ovaries 

 ofT, and so on. One theory after another 



was put to test, but regardless of theories 

 and their application, the Japanese 

 persimmon {Diospyros Kaki) has con- 

 tinued to act in the same manner — 

 producing flowers abtindantly, some- 

 times resulting in fruit, more often giv- 

 ing no harvest. 



WHY FRUIT FAILS TO SET. 



It was not until 1909 that attention 

 was called to the true cause of barren- 

 ness^ in D. Kaki and the year follow- 

 ing, the cause of sporadic fruitfulness 

 was learned. It was known years 

 before to a few" that the flowers of D. 

 Kaki are of two kinds, pistillate and 

 staminate, but that this fact had any 

 practical bearing on the problem of 

 unfruitfulness did not seem to occur to 

 anyone. 3^Iore recently^ the existence 

 of perfect flowers, i.e., those containing 

 both stamens and pistils, was brought 

 to light. These flowers have no prac- 

 tical bearing on the problem, as they 

 are rare and, from some cause or other 

 not yet clearly understood, their ovaries 

 very seldom develop into mature fruit. 

 Since 1909, the results of more than 

 twenty thousand hand pollinations have 

 fairly demonstrated that pollination 

 will cause fruit to set and grow to ma- 

 turity, when without it, no fruit would 

 be produced. 



The fruitfulness of certain trees or 

 groups of trees in some seasons and not 

 in others even when pistillate flowers 



•Hume, H. Harold. Xon-fruiting of Japan Persimmons due to lack of Pollen. Science, N. vS. 

 Vol. XXX No. 76. Sept. 3. 308-309. 1909. 



^Berckmans, P. J. Persimmons. Cyclopedia American Horticulture, 3. 1281. 1901; also 

 Van Deman, H. E. The Kaki. Report of the Commissioner of Agriculture, 1887. 642-64.S. 

 1888. 



^Hume, H. Harold. The flowers of Diosprvos Kaki L. F. Trans. Acad. Science St. Louis 

 Vol. XXII. No. 5. Dec. 31. 125-135. PI. XXV-XXXI. 1913. 



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