Mabch 10, 1921. 



The Florists' Review 



35 



£^ FOODS FOR FLOWERS <^ 



?<l»Wsffif;ffifs<Rfi^^ 



^'r?-*^"^4^1^r•^"r•\:y*YY*^1Y*Y,y*>(1lrSv1rr4iv1l)«^ 



THEEE are, in a general way, two 

 groups of materials which we add 

 to soil in order to make it more 

 productive. These two groups are nat- 

 ural manures and chemical fertilizers. 

 When we add fertilizers of any kind 

 to the soil, we do one or both of two 

 things: (1) We add to the soil sub- 

 stances which affect the physical prop- 

 erties oi the soil; (2) we add to the soil 

 chemical substances which are food 

 materials for the plant. 



These two requirements are the only 

 ones which we expect of fertilizers. 

 Natural manures in part fulfill both of 

 these requirements; chemical fertilizers, 

 only one. Farmyard manures improve 

 the physical character of soils (a) by 

 making soils that are clayey and com- 

 pact more open and porous, so that the 

 water and air can penetrate more freely, 

 and (b) by making soils that are light 

 and sandy more compact, by filling up 

 the open spaces. It thus enables light 

 soil to absorb and retain more water. 



In addition to the important effects 

 of manures on the physical structure of 

 soils, they furnish also food materials 

 for plants. Chemical fertilizers have, 

 as a rule, but one function, that of fur- 

 nishing food materials for the plants. 

 Their indirect effect is seldom useful; 

 sometimes it may even be harmful. 



Food Materials of Plants. 

 Plants require certain chemical ele- 

 ments in soil for food materials. All 

 told, there are only seven soil elements 

 that are necessary. A number of these 

 are ordinarily present in soil in suffi- 

 cient quantities, so that of the seven 

 essential elements only three are found 

 in our soils in insufficient quantities. 

 These three elements are (a) nitrogen, 

 (b) j)hosphorus, and (c) potassium. 

 We will omit potassium in this discus- 

 sion for it, too, is not ordinarily a limit- 

 ing factor. 



Nitrogen: Source and Availability. 

 When we say that a fertilizer is in 

 an available form we mean that it is in 

 a form that can be used by the plant 

 directly. It is soluble in water. When 

 we say that a fertilizer is in the un- 

 available form we mean that it cannot 

 be used by {)lants directly, but that it 

 must undergo certain changes in the soil 

 before it can be taken up by the jilant. 

 A fertilizer in available form can be 

 taken up and used by the plant imme- 

 diately; one in unavailable form can- 

 not be used immediately, but must first 

 go through a gradual process of decay 

 in the soil. 



Let us now take u]> some of the fer- 

 tilizers which furnish nitrogen. The 

 one most commonly used is barnyard 

 or stable manure. Stable manure varies 

 in composition. It contains large 

 amounts of nitrogen and, in addition, 

 it contains phosphorus and potassiiun. 

 All three of these elements are used by 

 plants. 



A ton of stable manure consists, ap- 

 proximately, of seventy-five per cent, 

 or 1,500 pounds, of water and twenty- 

 five per cent, or 500 pounds, of dry 

 matter. All the fertilizing material, 

 of course, is in the dry matter. The 



Tills paper, prepared by l)r. I'. .\. I^ilieiiliiuier 

 In cliiifKe of experimental work in tlio division of 

 floriculture at the University of lllln<>'»' '""n- 

 tains the substance of liis talk on What Our 

 Kertilizer Studies Have TauKlit Us," Kiven at the 

 meeting of the Illinois State Florists' Associa- 

 tion at UrlMina March 8. 



dry matter in one ton of average mixed 

 stable manure contains approximately 

 ten ponnds of nitrogen, five pounds of 

 phosphoric acid (2.2 pounds phos- 

 phorus), and ten pounds of potash (8.3 

 pounds potassium). 



Natural manures, therefore, contain 

 the three chemical elements most needed 

 by plants. However, natural manures 

 do not meet the entire demands of 

 plants. They fall -short from two view- 

 points. 



First, the fertility elements contained 

 in them are not in proper proportion. 

 The amount of nitrogen is excessive, 

 relative to the amount of phosphorus 

 and potash. If they are used in suffi- 

 cient quantities to meet tlie needs of 

 jihosphorus, there is a waste in nitrogen. 

 In other words, there is not enough 

 phos])liorus present. 



Secondly, the constituents contained 

 in natural manures are not in suffi- 

 ciently available form to provide for a 

 quick and continuous growth. In order 

 to get a quick response on tJio part of 

 the plant, large quantities must be ap- 

 plied and this again results in a waste 

 of nitrogen. 



Fresh Manure vs. Rotted Manure. 



Rotted manure contains more plant 

 food materials per ton than does fresh 

 manure. This is because fresh manure 

 shrinks in bulk during the decomposi- 

 tion process. A ton of the former will 

 shrink to one-half or two-thirds of a 

 ton of the latter. 



However, certain other changes take 

 ]ilace during the decomjiosition process 

 which affect greatly its fertilizing quali- 

 ties. Fresh manure contains, as a rule, 

 much soluble and, hence, available 

 nitrogen. During the decomposition 

 process a large percentage of this solu- 

 ble nitrogen is lost by leaching. From 

 one-fourth to one-half of the soluble 

 nitrogen may be lost by leaching and 

 by passing into the air in another 

 form. Another part of the nitrogen is 



changed during the decomposition 

 process from the soluble to the insolu- 

 ble form. Therefore, well rotted ma- 

 nure contains little, if any, active 

 nitrogen. 



The phosphorus compounds are af- 

 fected in a different way during the de- 

 caying process. They are changed from 

 the insoluble form to the soluble form. 

 Since phosphorus compounds cfo not 

 leach out readily, there is no loss, as 

 there is in the case of the nitrogen. 



Rotted manure, therefore, is a more 

 evenly balanced combination of plant 

 food materials. Generally speaking, the 

 phosphorus is available to a larger ex- 

 tent than in fresh manure. The nitro- 

 gen, however, is present in a less avail- 

 able condition. There is a relatively 

 larger amount of phosphorus and rela- 

 tively smaller amount of nitrogen pres- 

 ent than in fresh manure. 



Nitrogen in Three Forms. 



Natural manures cnntain nitrogen in 

 three forms, (a) organic nitrogen, (b) 

 ammonia and (c) nitrates. The organic 

 nitrogen — that is, the nitrogen found in 

 the straw and other vegetable matter — - 

 cannot be used by the plant directly as 

 food. This must first decay and change 

 into other forms. 



One of the jiroduets of this decay is 

 itmmonia. Ammonia is readily soluble 

 in water or, as a gas, it passes off 

 quickly into the air. In this form 

 nitrogen is readily lost. Plants do not 

 depend upon ammonia for their nitro- 

 gen; in fact, it is believed that little 

 ammonia is used by plants. The am- 

 monia which is formed during the 

 jirocess of decomposition of the manure 

 is changed into the third form, the 

 nitrate. 



Nitrates are the chief source of nitro- 

 gen for plants and, therefore, the most 

 important form of nitrogen compound. 

 Natural manures, therefore, in order to 

 be available to plants for food mate- 

 rials, must pass through tliesc stages of 

 decjiy. This jirocess of decay depends 

 upon conditions which are variable. 

 The quality and condition of the ma- 

 nure, the kind of soil, the temperature 

 and the soil moisture all enter into the 

 process. Therefore, keeping in iiiiml 



PRODUCTIO.N E.\CII YEAR. 



.Xverace 



Ktcm Totiil 



length tlowers 



Variety Treatment 3 years 191(5 17 



Ophelia Acid pliosplialc 1,S.93 4,847 



.\o acid iihospliate 13.13 4. ft")". 



Hoosier .\cid phospha tc 13.6.5 «'.r>0;{ 



.No acid phosphate 13.29 I'.tiOlt 



Killariioy Acid phosphate 9.fl« .'i.fMU 



No acid iiliosphatc 9.37 ,^.39."> 



White Killarm'y Acid iihosphato 10.01 5,18."> 



No acid phospha te 9.44 4,848 



Total 

 flowers 

 1917-18 

 3.988 

 3,60<; 

 l.*,4.')7 

 2.1.")8 

 ."..»«» 

 ."..l.>49 

 .".,280 

 4,729 



Number of 

 Variety plants 



Ol.helia 143 



144 



Hoosier 141 



144 



Killaniev 144 



144 

 Wliito Kill.irncv 144 



PIFFKUENCK IN TOTAL I-UOniTTION. 



Total 

 flowers 

 Treatment 1916 19 



Acid phosphate 12,827 



.No acid pliosphate 11,943 



Acid phospliatp 7,309 



No acid phosphate 6,014 



Acid phosphate 16,855 



No acid phosphate 1,'),713 



.\(id phosphate 16,111 



No acid phosphate 14,630 



all varieties 



Av 



144 

 Total increase in number of flowers for three years. 



Increase in averace number of flowers per plant 



Cost of acid phosphate used in the experiment (at present price) 



crage nui 



tier of 

 flowers 



89.70 



.82.93 



.'■.1.83 



41. 7(! 

 117.04 

 109.11 

 111.8ft 

 101. !>9 



Total 

 rtowerx 

 1918 19' 

 3,992 

 3.682 

 2.249 

 2.147 

 ."..615 

 r..069 

 .-..646 

 5,053 



Avcras<» 



Increase 



6.77 



1007 



7.93 



10.2» 



.4.802 

 .. . » 

 .$0.60 



Effect of Acid Phosphate on Flower Production of Roses. 



