292 



HOKTICULTURE 



April 10, 1920 



HORTICULTURE 



BatabUshed bj WllUam J. Stewart la IWM 



Vol. XXXI 



April 10, 1920 



No. 15 



PUBLISHED WKEKI.T BT 



HORTICJULTURE PUBLISHING COMPANY 

 T8 Devonahire Street, Boston, Maes. 



EDWARD I. FARRINGTON, Editor. 

 Telephone Fort HIU 86M 



ADV£RTI8IMO BATBS: 



Per Intb, SO Inohes to pace 91M 



Diieannt on Contracts for oonMentlTe tneertlou, as follow*: 



On* month (4 times), 6 per cant.: threo moatha (IS times), !• 

 yar eent. ; six months (26 times), io per eeat.) •■• year (62 Hmes). 

 M por eent. 



Pace and half pace space, not canaeeatlTa, i»ta* am appUeatlon. 



SUBSCRIPTION RATES: 



One Tear, In advance, |1.00: To Forelca Oonntries, »2.00j To 

 Canada, $1.S0. 



tatered as second-elass matter December 8. 1904, it tbe Poit Office 

 at Boston. Mass., under the Act of CoBgre^s ef March 8, 1887. 



Tlie daily papers have been making much of a 

 Lights report sent out from Washington regarding ex- 

 and periments made by experts of the Agricultural 

 Plants Department, which seem to show that plant life 

 depends more on light than temperature for Its 

 growth, and that flowering may be regulated to a large ex- 

 tent by the use of artificial light and means for excluding 

 sunlight. The report says that) the principle is revolution- 

 ary, but as a matter of fact, experiments have been made 

 by practical growers as well as by theorists, during many 

 years, to show the Influence of electric lights on plants. 

 The late W. W. Rawson. of Boston, at one time made many 

 experiments of this sort in his greenhouse at Arlington. 



At the same time it may be that discoveries have been 

 made which will prove of extreme importance to florists. 

 In any event, the work which is being done by the Depart- 

 ment of Agriculture will interest all commercial growers. 

 According to the Department's announcement, the flower- 

 ing and fruiting period of practically any plant can be 

 made to take place at any time of year by darkening the 

 greenhouse In the morning and evening if the day is too 

 long by lengthening the day by artificial light if the day 

 is too short. As it is now, these results are obtained in a 

 large measure by regulating the temperature. Easter lilies 

 are brought to maturity at just the right season by this 

 method. It was by this same method that the wonderful 

 .Japanese Azaleas which E. H. Wilson brought back from 

 the Orient were made to flower at exactly the week when 

 the big Boston show was held. 



Yet according to the Washington reports temperature 

 appeared to exert no influence in the tests made by the de- 

 partment experts. Experiments did show, though, it is 

 claimed, that too little sleep or in other words, too many 

 hours of daylight, were sufficient to prevent many plants 

 from ever reaching the flowering or fruiting stage. A 

 striking illustration of the relative importance of tempera- 

 ture is given in the fact that plants kept in the dark for 

 part of the day underwent in mid-summer the changes that 

 in nature come in the fall, and that heretofore have been 

 attributed to lower temperature. This was true, it is stated, 

 even when the dark house registered a higher temperature 

 than the outside atmosphere. 



Artificial light served to bring certain plants into 

 bloom much earlier than under normal conditions. Irises, 

 for example, given electric lights for eighteen hours a day, 

 bloomed in two months, while others in the same tempera- 

 ture, but without artificial light required months longei". 



"The length of the day" the department announcement 

 says, "is proved to be the most potent factor in determin- 

 ing the relative proportions between the vegetative and 

 fruiting parts of many crop plants. Indeed, fruiting may be 

 completely suppressed by a day too long or too short. This 

 new principle undoubtedly explains the erratic behavior 

 which has been observed with many crops when they are 

 shifted to different latitudes." 



The scientists used dark chambers by which they 

 shortened or lengthened the life cycle of plants, and 

 forced some of them to complete two cycles in one season. 

 These reported, results are quite different, of course, from 

 what florists have been taught to accept. It will be hard 

 even now for them to believe that temperature is not a 

 matter of importance. They will ask, perhaps, how it 

 happens that the Japanese witchhazels, which in warm 

 winters bloom in the Arnold Arboretum in January or 

 February at the latest, did not bloom this season, after a 

 long, cold winter, until March. They may also ask an ex- 

 planation oB the fact that in England, where temperatures 

 have been unusually mild the past winter, many of the 

 common shrubs are flowering long ahead of their usual 

 dates. It may be said that the winter in this country has 

 shown more dark days than usual, and that in England 

 less, but that would hardly be a satisfactory explai^tion of 

 the great difference in blooming time. On the whole, it 

 must be admitted .that the light averages about the same 

 each season. 



Perhaps, however, we have not yet received the whole 

 story from Washington. It is quite possible that the use 

 of artificial lights will indeed revolutionize the growing of 

 both flowers and vegetables under glass. New and unex- 

 pected developments may come at any time. We are no 

 longer surprised at them or inclined to belittle them until 

 their value has been determined upon by practical experi- 

 ments. It may be that in the future every greenhouse will 

 have its special lighting arrangements, and that growers 

 will have to study the effects of light and darkness from a 

 new viewpoint. 



It may be, as the papers say, that the peak has 

 Higher been reached in the steadily increasing cost of 

 Prices supplies in many lines, but It is not easy to see 



where this applies to the florists' business. Take 

 the item of coal alone. Where ordinarily a drop may be 

 expected at this season as an inducement for early buying, 

 we find a startling advance instead, with no prospect of any 

 drop at all. The coal situation is one which means much 

 to every grower. It takes a large part of his income to 

 pay the coal bill at best. Coal he must have, though, if he 

 is to do business at all, and with railroad matters in their 

 present chaotic condition there is no assurance that coal 

 will move at all freely for many months to come. As a 

 matter of mere discretion, therefore, it would seem wise 

 to get in one's order even though the price be high. 



Then it is much the same with supplies from abroad. 

 Every report from France and Germany shows that chiffon 

 is on the advance, and that very much higher prices are 

 bound to prevail. In fact, foreign markets all along the 

 line are rapidly tagging that of this country. The nursery- 

 men have found that out when they have tried to buy stock 

 of any kind, even fruit stock. 



Express rates ar6 on the advance, too, so that every- 

 thing considered, there is little hope of cutting costs for 

 a long time. 



