36 



The Rorists' Review 



Mabch 10, 1921. 



tliis variable but necessary process of 

 decay and also the more or less unbal- 

 anced ratio of elements in manure, it 

 is, from tlie standpoint of economy as 

 well as results, a good practice to sup- 

 plement natural manures with the so- 

 called artificial manures. 



We must remember that nitrogen is 

 the most ex2)ensive of all the fertiliz- 

 ing elements. This is true because the 

 amounts ordinarily available in nature 

 are small; because it is the element of 

 the soil which is most heavily used by 

 plants, and because it is the most elu- 

 sive, since it changes sooner or later 

 into some form that is easily lost to soil 

 and plant. 



Dried Blood as Fertilizer. 



One of the best su])plemeuts of nat- 

 ural manures is dried blood. It is one 

 of the most concentrated and one of the 

 richest in nitrogen of the organic nitro- 

 gen-bearing fertilizing materials. Rod 

 dried blood is uniform in composition. 

 It contains thirteen to fourteen per 

 cent nitrogen. The market product is 

 standardized and guaranteed to contain 

 a certain amount of nitrogen. Black 

 dried blood is less concentratediand less 

 uniform in composition, due to less 

 careful methods of preparation. It con- 

 tains from six to ten per cent nitrogen 

 and soniotinies as much as four per cent 

 phos]>h()ric acid. 



Dried blood is one of the best organic 

 fertilizers, because its jihysical char- 

 acter is such that decay in the soil is 

 rapid. Dried blood is not immediately 

 available 1o plants; it cannot be taken 

 up directly by the roots, but it must 

 first decay and change into the nitrate 

 form. However, under favorable con- 

 ditions of moisture and temperature 

 this decay is rajiid and the nitrogen 

 thus becomes available after a short 

 ])eriod of time. 



If wo rc])resent the availability of one 

 of our most available forms of chemical 

 fertilizers, c; nitrate of soda, by 100, 

 the availability of dried blood would 

 be a]iproximately sixty-five or seventy. 

 On this same basis the availability of 

 average rotted barn manure would be 

 approximately twenty-five to thirty- 

 five. 



This shows the manner in which dried 

 blood is a good supplement of natural 

 manures. Dried blood supplies the 

 plant with nitrogen quickly; it makes 

 for a rapid and continuous growth by 

 making up the deficiencies of natural 

 manures. 



Phosphorus Fertilizers. 



We will now discuss another class of 



fertilizers, those which supply phos- 

 phorus for the plant. Plants must have 

 l)hosphorus. This element is needed in 

 the formation of all young cells, such 

 as are found in the young root tips and 

 in developing flower buds. Nitrogen 

 and phosphorus are equally essential 

 and both are, therefore, important from 

 the standpoint of fertilizers. 



It is important that we understand 

 the terms used for the various kinds of 

 fertilizers containing phosphorus. The 

 materials used as phosphorus fertilizers 

 are of two kinds, the mineral phosphates 

 and the organic phosphates. 



The mineral phosphates are obtained 

 by grinding rock which contains phos- 

 ])horus in quantity. Rock phosphate 

 contains the phosphorus in chemical 

 combination with calcium. Chemically 

 it is known as tri-calcium phosphate. 

 The im])ortant fact to remember is that 

 rock phosphate is practically insoluble 

 in water, one part requiring for solu- 

 tion approximately 50,000 parts of pure 

 water. In the soil it is somewhat more 

 soluble, this depending on the presence 

 of other substances. Because of its low 

 solubility, rock phosphate is not readily 

 available to plants. 



in order to make rock phosphate 

 soluble, and hence available, it is 

 treated with sulphuric acid. The sul- 

 ]ihuric acid acts chemically on the rock 

 phosphate and forms two substances, 

 acid phosphate and gypsum. This mix- 

 ture is sold as a fertilizer under the 

 name of acid phosphate or superphos- 

 ])hate. Acid phosphate is not found 

 naturally, but is to be had only as a 

 )nanufactured product. One hundred 

 pounds of purchased acid phosphate 

 contain approximately forty-six pounds 

 of actual acid phosphate and fifty-four 

 pfiunds of gyjisum. The important fact 

 1o remember concerning acid phosphate 

 is that it is soluble in water. One part 

 dissolves in 100 ])arts of water. Not 

 only is it soluble in water, but it is also 

 available to plants. 



Acid phosphate is not a completely 

 stable compound. It has the character- 

 istic of changing, under certain condi- 

 tions, into what is \nown as the re- 

 verted form. In this form it is less 

 soluble. However, it is still available 

 to a high degree and can still be taken 

 up liy plants. 



Let me call to your attention at this 

 time a difference betw^een the soluble 

 nitrogen compounds and the soluble 

 acid phosphate. Nitrogen, when ap- 

 plied to the soil in soluble form, remains 

 soluble and in this condition readily 

 leaches from the soil. A great waste 

 may result, therefore, if too large quan- 



Totnl 

 Trcitnioiit flowt-rs 



.\fitl pliospliMto 7.079 



Nil fKirl pliosphato (5,482 



.\(i(I i)liosplmto .I.O.'iT 



No ncid pliospli.Tte 5,893 



Total Increase In niimI>or of flnncrs for one yonr, two varieties 001 



Increase In avpniRe number of flowers per plant ■•• 



Cost of acid phospliate used In the experiment (at present price 



Number of 

 Variety plants 

 Enchantress 342 



Champion -69 



281 



Averace 



per 



plant 



L'o.r.n 

 lit.uil 

 22 ir, 

 20,97 



Average 



increase 



per plant 



1 .10 



1.18 



1.28 



$33 per ton) $.5.04 



Effect of Acid Phosphate on Flower Production of Carnations. 



Niiml)er of 

 Variet.v plants 



Killarne.v 144 



144 



Richmond 1-1-t 



144 



.'^^ai:i' 



plant 

 4.1. •-'7 

 .34.88 

 3.-). 13 

 28.35 



.\vera;ie 



increase 



per plant 



10.39 



0.78 



Total 



Treatment "o'-i'n'* 



Acid phosphate ^-^^ 



Hone meal ^'"-^ 



Acid phosphate -^Y™ 



r.one meal '*'"'*1 



Total Increase in number of flowers for one .vear, two varieties 2 475 



Increase in average number of flowers per plant, two varieties 8.W 



Cost of acid phosphate (40 lbs. l>er 100 sq. ft.) «» $15 per ton 5-.40 



Cost of bone meal (21.4 lbs. per 100 sq. ft) at $28 per ton .; • •^■4" 



Phosphorus applied as acid phosphate, per 100 sq. ft -••: ";' 



rhosphorus applied as bone meal, per 100 sq. ft - '• ' '"'• 



A Comparison of Acid Phosphate and Bone Meal on Roses. 



titles are ai)plied. With soluble phos- 

 phates the danger of loss or waste is 

 not great. If applied in too large quan- 

 tities, soluble phosphates tend to be- 

 come insoluble, or to revert, as we ordi- 

 narily say. Acid phosphate does not 

 leach out of the soil. 



Experiments with Acid Phosphate. 



We have been carrying on some ex- 

 periments with the view of determining 

 the results that may be obtained by 

 the use of acid phosphate in rose and 

 carnation soil. The results of a 3-year 

 test with roses and a 1-year test with 

 carnations are given in tabular form 

 herewith. A complete account of the 

 method employed in the experiments 

 will be published later in bulletin 

 form. 



The tables below show some striking 

 results. The application of acid phos- 

 ])hate resulted in increased production 

 for each variety and the increase is 

 consistent, in the case of the roses, for 

 three successive years. A total of 1,152 

 rose plants and 1,440 carnation plants 

 were used in the experiment. The 

 benches of the two houses in which the 

 work was conducted were divided into 

 sections, sixteen rose plants and twenty 

 carnation plants growing in each sec- 

 tion of the two houses, respectively. All 

 sections of each house received the same 

 treatment, except that each alternate 

 section received one application of acid 

 phosphate, while the remaining sections 

 received no acid phosphate. 



Bone Phosphate. 



Another form in which phosphorus 

 occurs and which is used as a fertilizer 

 is bone meal. The phosphorus of bone 

 is in combination with organic matter 

 and differs in this respect from the phos- 

 ]ihoru3 compounds already discussed. 

 Good bone meal should contain on the 

 average about twenty-two per cent 

 phosphoric acid. In addition, it con- 

 tains about four per cent of nitrogen. 

 Steamed bone contains relatively more 

 phosphoric acid, from twenty-eight to 

 thirty per cent, but only from one to 

 two per cent nitrogen. 



Many florists use bone as a fertilizer. 

 It is unquestionably a good fertilizing 

 material, for it contains much phos- 

 phorus and it is, therefore, a valuable 

 source of phosphoric acid. However, 

 bone is not soluble and the phosphorus it 

 contains is not in a form which is imme- 

 diately available to plants. Bone must 

 decay before the phosphorus becomes 

 available. Steamed bone is more directly 

 before the phosphorus becomes avail- 

 able. Steamed bone is more directly 

 useful to plants than is the raw bone 

 meal, because, since it is in a finer state 

 of division, it decays more rapidly. The 

 rate of decay, as in the case of stable 

 manure, depends upon variable factors, 

 such as moisture and temperature. 

 Bone, then, differs from acid phosphate 

 as a fertilizer in the fact that the 

 former is soluble and immediately avail- 

 able to plants, while the latter is less 

 soluble and not immediately available. 



We have carried out an experiment 

 to test the comparative efiiciencies of 

 acid phosphate and steamed bone meal 

 in the flower production of roses. The 

 results are giVen in tabular form on 

 this i)age. The applications of the two 

 fertilizers were such that approxi- 

 mately equal quantities of phosphorus 

 were applied. Acid phosphate was ap- 

 plied at the rate of forty pounds per 

 hundred square feet. In order to obtain 



