770 



HORTICULTURE, 



May 29, 1909 



aiii, a fine distinct perennial, flowering 

 in Match, April and May, has a bell- 

 shaped flower of mauve purple with 

 yellow anthers, found on the Chiltern 

 Hills, and the downs of Surrey and 

 Sussex, dotted over the turf. In such 

 positions, it just shows through the 

 short grass, but in sheltered places, 

 even there it develops to a larger size 

 and flowers abundantly. In the rich 

 soil of a garden the plant is much 

 moro vigorous and freer flowering. 

 There are white, red and lilac varieties. 



The above-named species and varie- 

 ties of Anemones are the more gen- 

 eially cultivated in English gardens. 

 A. Halleri is a late form of A. Pulsa- 

 tilla. FREDERICK JIOORE. 



London. 



SOME OF OUR PROBLEMS AS 



ROSE GROWERS. 



A pai>pr prepared by Prof. L. C. Cor- 

 bett of tlie Huroau of Agriculture, Wash- 

 liiijtoii. l>. C, for the Aunual Meeting of 

 the ."Vncrican Rose Society, Mar. 16-18, 

 1909, hekl at Buffalo, N. Y. 



Heat, light, water and soil are the 

 big four with which the plant grower, 

 be he farmer, gardener or florist, is 

 concerned. In nature all of these fac- 

 tors are more or less in the class of 

 variables. The farmer and gardener 

 working in the open and dependent 

 upon natural sources for heat, light, 

 moisture and soil are playing at a 

 game of chance. The two factors that 

 it is within his power to modify are 

 moisture and soil. By irrigation the 

 water content of the soil can be regu- 

 lated. By the judicious use of fertiliz- 

 ers and manure the food supply of the 

 plant can be modified. Aside from 

 these two alternatives the farmers and 

 gardeners are totally dependent upon 

 nature's kind provisions. The florist 

 carries the cultivation of plants one 

 step further from the field of chance 

 by safeguarding the temperature fac- 

 tor. The florist may or should be able 

 to control three of the determining fac- 

 tors in plant growth, viz., heat, mois- 

 ture and soil. His variable should be 

 confined to the light factor alone. Our 

 modern greenhouses have been well 

 planned so as to cut out as little light 

 as possible by the use of light frame- 

 work and large glass. The great 

 weakness in our present scheme of 

 greenhouse construction lies in the to- 

 tal disi-egard of the laws of reflection 

 and refraction. The fact that a glass 

 roof can be so constructed that it will 

 allow a very large percentage of light 

 and heat rays of the sun to penetrate 

 the house at certain hours of the day 

 and to reflect or throw oft a large per- 

 centage of the same rays at other 

 hcurs of the day, has, it would appear, 

 been given altogether too little con- 

 sideration both by florists, physiolo- 

 gists and physicists. This is one of 

 the respects in wlueh practice is far 

 behind. The available knowledge on 

 this phase of construction seems to 

 have been almost entirely ignored by 

 the practical florist and greenhouse 

 builder. Much thought is spent in de- 

 signing gutters, sash bars and venti- 

 lating apparatus, while the pitch of 

 the roof and the direction of the ridge, 



factors which directly measure the 

 value of the houses, are entirely ig- 

 nored. It is therefore evident that the 

 florist may in a measui-e at least in- 

 fluence the light factor. While he can- 

 not increase or decrease the actual 

 hours of sunshine, he can by properly 

 planning his houses afford his plants 

 the maximum benefit of the light pro- 

 vided in nature. Researches which 

 have been conducted along this line 

 clearly indicate the value of light as a 

 factor in plant growth. Prolonging 

 the light period by artificial means as 

 has been demonstrated by Bailey, 

 Hane, the writer and others, decidedly 

 hastens growth. Should we not then 

 give this factor the full attention its 

 importance deserves? 



The temperature and moisture re- 

 quirements of plants are given far 

 more consideration than light by flor- 

 ists, but it is surprising to note the 

 great lack of available general infor- 

 mation upon so simple a matter of 

 properly providing tor the requisite 

 amount of radiation in a greenhouse 

 for a particular purpose in a definite 

 locality. Too often this impo[tant 

 matter is left to the local plumber, 

 who has no idea of the problem in- 

 volved, or how to solve it. Yet heat 

 is the greatest charge against the 

 growing account. 



Moisture is the coin of the realm 

 with the gardener and the florist; both 

 deal in products the chief constituent 

 of which is water. A pure and ade- 

 quate water supply intelligently used 

 is a determining factor in garden and 

 floral undertakings. Now we come to 

 the soil, an absolute essential to the 

 success of ever>- commercial agricul- 

 tural enterprise, the source of the live- 

 lihood and wealth of the major por- 

 tion of the earth's inhabitants; yet 

 what shall we say of it, it is so com- 

 plex? If we consider its derivation we 

 find the rocks yielding to the action of 

 frost, water and air to supply the min- 

 eral matter, vegetation springs up to 

 ripen and decay, and thus contribute 

 humus, another factor as important as 

 the mineral. The decomposition o£ 

 organic matter in the soil sets to work 

 other forces which are no less impor- 

 tant than the primarj' constituents 

 themselves. The combination of the 

 oi-ganic and the mineral substances 

 creates a condition which makes it 

 possible for many low forms of ani- 

 mal and plant life to exist in this me- 

 dium we call soil. These low form? 

 are some of them helpful and some of 

 them hindrances to the plant grower. 

 The introduction of this host of ten- 

 ants complicates things and renders 

 what was formerly thought to be sim- 

 ply a chemical problem, a very intri- 

 cate, combined chemical and bacterio- 

 logical puzzle. Some aspects of ibis 

 puzzle are yet so new and difficult that 

 no prediction dare be made at this time 

 regarding their importance to agricul- 

 ture. Enough has been determined, 

 however, to prove that an important 

 lead has been struck. The value of 

 nitrogen gathering bacteria is suffi- 

 cient evidence of the richness of this 

 new field. Knowledge of the way in 

 which nitrogen gathering bacteria 

 woi-k gives us a clue to the solution 

 of one of the most difficult problems in 

 the maintenance of soil fertility. It 

 explains the division of labor in na- 

 ture and gives a reason for crop rota- 

 tion. The same laws that govern the 



rotation of crops in field operations 

 come into play to our advantage in the 

 soil heap. The compost heap should 

 consist of organic material in the form 

 of sods and manure so combined with 

 mineral matter in the form of loam 

 and clay as to enable decomposition 

 and nitrification to take place rapidly. 

 The florist's business is not merely to 

 place available food in a natural soil, 

 but to combine the several constituenis 

 for fertile soil in such manner as to 

 secure that mechanical condition and 

 lood supply calculated to best meet the 

 requirements of the particular crop un- 

 der consideration. In this respect the 

 florist has an advantage again over the 

 gardener and the farmer. But can 

 any one desciibe the ideal soil for any 

 particular crop? Can any one say that 

 a soil consisting of 10 per cent, organic 

 matter, 30 per cent, clay, 40 per cent, 

 loam and 20 per cent, sand is an ideal 

 soil for roses, for carnations, for let- 

 tuce, or for any other crop? I think 

 not. Our knowledge upon these im- 

 portant points is of the empirical kind. 

 An experienced gardener makes up a 

 potting soil; he mixes it with his 

 hands, and if it appears too heavy he 

 adds sand; if not sufficiently fibrous, 

 he adds leaf mould or peat; just why 

 he adds these substances he cannot tell, 

 neither can he describe to you the ex- 

 act consistency and character of his 

 ideal rose soil; yet his knowledge of 

 the requirements of a particular crop 

 leads him to make the changes above 

 noted to bring the soil to his ideal of 

 the requirements for the particular 

 crop. Can this empirical knowledge 

 or idea be reduced to exact terms? Is 

 the exact amount of available plant 

 food and the proportion of sand, clay, 

 humus in this ideal soil measurable? 

 If it is we can obtain a basis for ex- 

 act experiments to determine whether 

 or not the gardener's judgment of an 

 ideal soil for a particular crop is cor- 

 rect. If these factors are not meas- 

 urable we are as much at sea in our 

 experimental work as is the gardener. 

 It is all simply a matter of judgment. 

 Up to the present I am sori'y to say 

 that the whole matter is largely de- 

 pendent upon experiences and judg- 

 ment. Soils differ so in composition 

 and physical properties even when, so- 

 called, like materials are used in their 

 make-up, and we know so little regard- 

 ing the influence of bactei-ial action 

 which is consistently working in the 

 soil that it is practically impossible in. 

 the present state of our knowledge to 

 reduce the soil factor to exact meas- 

 urement. A much more accurate idea 

 of the relative influence of hear, light, 

 water and soil can be secured under 

 greenhouse conditions than in the 

 open, but even here, while we know 

 infinitely more than did the early gar- 

 deners, our knowledge is far from ex- 

 act. It may be that exact data will 

 never be possible, but certain it is that 

 the knowledge that is so rapidly ac- 

 cumulating will clear up many dark 

 places and we hope soon put us in pos- 

 session of facts to replace empiricism. 

 Until more knowledge is available we 

 must continue, each to determine for 

 himself under his own environment, 

 the most profitable combination for the 

 compost and the varieties best suited 

 (o this soil and his market. "There is 

 no royal road to knowledge." and the 

 intelligent, painstaking care is the- 

 only way to spell success. 



