FEBRUARY 16, 1S99. 



The Weekly Florists' Review, 



277 



drawn and throw up flowering shoots. 

 Herein we believe lies the secret of 

 whether we are going to make a suc- 

 cess of our indoor grown plants, for if 

 not systematically pinched back they 

 become straggling and with no bottom 

 or foundation to them. 



The plants we set out last season on 

 June 20th were by Sept. 1st a solid 

 mass of fine wood from one end of 

 the house to the other, and not a dis- 

 eased plant among them. Twenty will 

 easily cover the total loss from stem 

 rot out of eight thousand plants dur- 

 ing the entire season. About the mid- 

 dle of September the plants are ready 

 for staking, after which a thin mulch 

 of well rotted cow manure is put on, 

 and from this on the usual winter cul- 

 ture is given them. 



These lines are not intended to im- 

 ply that the only way to get fine carna- 

 tions is to grow them under glass 

 throughout the entire season, for it is 

 demonstrated .on every hand that 

 grand stock is being produced from 

 plants lifted from the field, but which- 

 ever method is adopted, the only way 

 to attain success is to keep everlast- 

 ingly watching each little detail and 

 requirement of your plants. 



SUB-WATERING AND DRY AIR IN 



GREENHOUSES. 



Bv J. C. Arthur, of the Purdue Experimental 

 Station. 



[Read before tlie Philadelphia Meeting of the 

 .American Carnation Society.] 



The time was when acceptable 

 greenhouse culture called for a maxi- 

 mum growth without close inquiry 

 into the question of healthy and nor- 

 mal development. The ideal of the 

 gardener was a tropical jungle with 

 steaming atmosphere and a wealth of 

 luscious foliage and flower. 



The use of glass houses for winter 

 production of vegetables and flowers, 

 delighting in cool weather, such as 

 lettuce, radish, rose and carnation, 

 brought with it some modification of 

 the tropical ideal. But doubtless the 

 mt>.st potent factor in changing the 

 point of view has been the pressing 

 necessity for protection against the 

 many destructive parasitic diseases. 

 When the rust, smut, rot or mildew 

 carried off a crop, as it did much oft- 

 ener and more completely than in the 

 open air, an inquiry infio the causes 

 of the epidemic revealed advantages 

 in methods that eliminated the condi- 

 tions that favored the growth of the 

 fungus as fully as could be done with- 

 out interfering with the growth of the 

 crop. Incidentally it was learned that 

 the old-time notions regarding green- 

 house methods could be profitably 

 modified, and a spirit of inquiry and 

 willingness to change has been engen- 

 dered, especially a desire to adapt the 

 conditions to the fundamental needs 

 of the crop grown, if such knowledge 

 can be obtained. 



In citing the chief factors in chang- 

 ing the ideals in greenhouse culture 

 one must not forget the subtle but po- 



tent influence of the long stemmed 

 flower. To meet the demands of fash- 

 ion for a large flower upon a strong 

 leafy stem of considerable length, 

 very fortunately a demand that rests 

 upon a healthy taste, although one 

 that is sometimes carried to extremes, 

 the florist has been obliged to inquire 

 into the conditions that especially pro- 

 mote a vigorous yet substantial de- 

 velopment. Besides producing a large 

 flower upon a long stem, thorough 

 business success requires that the pet- 

 als be of a lasting texture and the 

 stem firm and substantial, and that 

 each plant shall produce a maximum 

 number of such blooms continuously 

 for the season. Only highly bred 

 plants, strengthened along every her- 

 editary channel, kept under condi- 

 tions for well-balanced and healthy 

 development, can meet these exacting 

 requirements. 



A clear conception of the problem 

 shows some radical defects in the old- 

 time methods of rearing plants under 

 glass. A year ago, in my paper before 

 this society under the caption, "Moist- 

 ure the Plant's Greatest Require- 

 ment," I presented reasons for believ- 

 ing that for the flowers and vegeta- 

 bles usually grown in commercial 

 greenhouses, wrong ideas prevailed re- 

 garding the distribution and applica- 

 tion of moisture. I pointed out that 

 the plant would thrive best, especially 

 the carnation, when the air was mod- 

 erately dry, and the soil moist be- 

 neath and dry on the surface. To se- 

 cure these conditions I advocated the 

 abandonment of surface spraying and 

 watering, and the substitution of uni- 

 form watering from beneath the soil. 



My experience in presenting new 

 methods to those who should presum- 

 ably take the liveliest intere.st in them 

 does not lead me to be sanguine of 

 much support. I am often reminded 

 of an attempt I once made to do a 

 service to some elderly persons who 

 lived in a small town away from the 

 direct lines of railway. Bananas were 

 practically unknown in that region, 

 and upon visiting them I carried some 

 along at considerable inconvenience to 

 myself. I expatiated upon the merits 

 of the new fruit, but my friends would 

 only take very small nibbles, and 

 promptly came to the conclusion that 

 they did not care for it, and said that 

 I had better eat it myself, if I thought 

 it was good. Some years afterward, 

 when the town had grown and the 

 shops were abundantly stocked with 

 imported fruits, I paid a visit to the 

 same old folks and found that bana- 

 nas had become their special delight, 

 and to live without them was a hard- 

 ship. 



So I had thought that subwatering, 

 especially in large and progressive es- 

 tablishments, might come about in 

 time, and naturally have been greatly 

 surprised and gratified to learn that 

 on the contrary it has been taken up 

 with promptness, both by large and 

 small growers, and not at all in a gin- 

 gerly manner, but on a scale that is 



likely to demonstrate its good and 

 weak points with reasonable clearness. 

 The present paper is intended as a 

 supplement to the former one, to 

 strengthen some of the theoretical 

 point.s and to amplify some of the 

 praotical details. In the first place I 

 wish to call your attention to an able 

 paper by Dr. W. Wollny upon the in- 

 fluence of atmospheric moisture on the 

 growth of plants, published a few 

 months ago. The work was carried on 

 at Munich in the experimental grounds 

 of the Bavarian Agricultural College. 

 Farm crops growing in the open field, 

 including alfalfa, hairy vetch, barley, 

 flax and potato, were used; and in or- 

 der to control the amount of moisture 

 in the air the experimental plants were 

 covered with small houses, about three 

 feet by six and five feet high, having 

 glass on three sides. These houses 

 were in groups of three, one having air 

 like the outside air. one having it 

 more moist and one much drier. 

 The plants were enclosed and observa- 

 tions taken throughout the whole 

 growing season, the houses being large 

 enough to permit normal development. 

 The extra moist air 'was secured by al- 

 lowing water to drip upon blotting pa- 

 per, and the extra dry air by using an 

 absorbent like chloride of calcium. 

 The work was well carried out and the 

 results can evidently be accepted with 

 confidence. 



The -well established conclusions 

 may be summed up in a few sentences, 

 the details not being especially impor- 

 tant in this connection. It is particu- 

 larly interesting to learn that the ash 

 content is always greater in plants 

 grown in dry air, and even the dry 

 weight is usually more, which, being 

 interpreted, means that in the dry air 

 more w^ter passes up through the 

 plant, bearing with it more food mate- 

 rial derived from the soil, and that 

 this induces an increased production 

 of solid matter in the plant. 



All parts of the plant become firmer 

 in dry air, the woody fibers increase in 

 strength, and the cuticle in thickness. 

 This insures a more substantial devel- 

 opment, and in most oases brings about 

 a heavier harvest. It is exactly in lino 

 with the aims of the florist, who 

 wishes cut flowers that will ship well 

 and that will stand up well in heated 

 rooms. 



A feature that is not so acceptable 

 was the shortening of the stems and 

 contraction of the leaves in the dry 

 air, which was very marked in every 

 trial. This is undoubtedly due, as the 

 author has indicated, to the loss of 

 water from, the foliage being so great 

 in the dry air that the roots were un- 

 able to take it up fast enough from 

 the soil to maintain the internal pres- 

 sure, which necessarily prevented the 

 cells from duly expanding. That the 

 difference in size of the organs was 

 chiefly due to a deficiency of water 

 supply is also evidenced by the failure 

 of the potato tubers to properly in- 

 crease and fill with starch in plants 

 grown in dry air. Of course it re- 



