206 



HORTICULTURE 



August 15, 190S 



too early to speak with entire confi- 

 dence as to results, though success has 

 been achieved in many cases, and the 

 striking results obtained may well 

 carry a lesson for florists whose car- 

 nations are suffering from drought in 

 the field. 



Soil and Temperature. 



The whole State is blessed with 

 abundant sunshine both in summer 

 and in winter and, except in the moun- 

 tainous portions, the winter climate is 

 mild with but little snow. There is a 

 wide daily range of temperature, 

 nights being cool in summer and cold 

 in winter. There is also a great dif- 

 ference between the temperature in 

 the sun and in the shade, largely due 

 to the absence of moisture in the at- 

 mosphere. Naturally in a climate so 

 •widely different from the climate of 

 the eastern states, problems arise pe- 

 culiar to this locality. 



In any arid region the vegetation is 

 scanty, and this same condition has ex- 

 isted back during the countless years 

 in which the surface soil was being 

 formed. Consequently the soil con- 

 tains very little fibre and very little 

 decayed vegetable matter, but the 

 soluble salts are apt to be present in 

 large quantities, because there has 

 been little water to dissolve them and 

 wash them away. Some of these salts 

 are beneficial and some of them are 

 harmful. In many localities alkaline 

 salts are present in such quantities as 

 to make the soil utterly useless, and 

 the water of the streams naturally par- 

 takes of the chemical qualities of the 

 soil so that in a great many cases the 

 water is so badly impregnated as to be 

 utterly unfit for use. Many florists in 

 the arid region have failed because 

 they neglected to investigate the 

 quality of their water supply before de- 

 ciding upon a location. 



It is generally possible to find soil 

 which will produce good roses in the 

 field, but it is difficult to find it heavy 

 enough to be satisfactory and at the 

 same time porous enough to permit of 

 heavy watering in the benches. Our 

 heaviest soil, called adobe, formed 

 from decomposed shale, is certain to 

 contain alkali, and cracks very badly 

 when dry; but by a careful selection 

 of soil most growers are meeting with 

 fairly satisfactory results, although 

 there is still much to be desired and 

 the ideal soil has not yet been ob- 

 tained. 



Manipulating the Soil. 

 It Is not an expensive or a difficult 

 matter to secure a determination of 

 the soluble salts in a sample of water, 

 and the Agricultural Department will 

 furnish valuable advise in such cases 

 If requested. When it comes to an 

 analysis of the soil, the situation is 

 very different, for then the problem 

 becomes very complex, and what with 

 soluble and insoluble food, moisture 

 content mechanical condition, and 

 nitrifving and denitrifying bacteria in 

 numerous varieties, the layman search- 

 ing for information becomes confused 

 and is quite ready to agree with a 

 recently published statement of Prof. 

 Corbett to the effect that the plant it- 

 self must tell you by its action whether 

 the soil is suitable. Yet even the soil 

 sharps quarrel among themselves, and 

 many of them claim that soil analysis 

 Is a safe guide. Your Illinois Experi- 



ment Station seems to be among the 

 latter, and more than that, they sup- 

 port their claim by results which lead 

 us to hope that the present confusion 

 will some day crystalize into tested 

 and accepted methods whereby the 

 man in the laboratory may give wise 

 counsel to both the man with the hoe 

 and the one with the hose. 



Owing to the exceedingly dry atmos- 

 phere and the light rainfall, it is very 

 difficult to get good results from the 

 composting of soil in Colorado. If sod ■ 

 is piled up it does not rot but dries 

 out. If manure is mixed with the soil 

 its chemical condition remains un- 

 altered for a long time. Some of our 

 rose growers have on that account ab- 

 solutely abandoned the use of manure 

 in soil put into the benches, and all 

 growers use it with great caution. 

 When used as a top dressing it should 

 be mixed with about an equal quan- 

 tity of soil. It is safe to say that if 

 a rose grower in Denver were to top- 

 dress his benches with such quantities 

 of green manure as is used in the 

 vicinity of Chicago, he would hardly 

 have a leaf left on any of his plants 

 at the end of a week. We Denver 

 growers are simply amazed at the im- 

 punity with which manure is used in 

 this vicinity. 



Some Ever Present Evils. 

 Among the ordinary evils which rose 

 growers have to contend with there are 

 none of them which we do not have. 

 The dry air seems to suit the red spider 

 to perfection, but with our continual 

 sunshine we are able to syringe the 

 roses freely without any bad effect. 

 Blackspot attacks the Beauties and Hy- 

 mid Teas to some extent, but is not 

 nearly the scourge that it is in the 

 east. Thrips are like the poor, and 

 are always with us, though I cannot 

 vouch for as many varieties as your 

 Illinois Experiment Station claims; 

 and the greenfly propagates as freely 

 with us as elsewhere, but is eradicated 

 long before we get rid of the thrips. 

 Mildew has been quite a problem with 

 us in August and September. In the 

 summer time our houses not infre- 

 quently show a temperature of 110 de- 

 grees when they are not shaded, al- 

 though it is very rare indeed that the 

 weather bureau reports any tempera- 

 ture above 95 degrees, and some of our 

 September days are nearly as hot as 

 midsummer. We frequently get a 

 night temperature in June, July and 

 August of 45 degrees, with 6 or 7 de- 

 grees lower than that on rare occasions, 

 and we expect a severe frost about the 

 middle of September. At the place 

 where I have charge, we keep steam 

 in the boilers all through the summer, 

 believing that it pays to do this as a 

 protection against mildew; and yet, 

 last summer we had a great deal of 

 mildew, while one of our neighbors 

 did not fire at all and his stock was 

 perfectly clean. Owing to the dry air 

 one would naturally expect us to be 

 free from this trouble, and I am not 

 competent to say why we are not. 



Own-Root and Grafted Roses. 

 A number of years ago our tea roses 

 were not producing well, and were not 

 making a good growth. Investigation 

 disclosed the presence of immense 

 number of eel worms. Our dry climate 

 and our mild winters seem to be just 

 suited to the production of nematodes 



in the open ground. After a very thor- 

 ough comparative test, we abandoned 

 the growing of tea roses on their own 

 roots, and have now for a number of 

 years grown them only on Manetti. 

 For a considerable time we sterilized 

 the soil that we put in the benches, 

 but this process has been abandoned as 

 the Manetti stocks have seemed to be 

 perfectly immune. I believe that a 

 large proportion of the tea roses grown 

 in Colorado are now grown on Manetti 

 stocks. 



The growing of American Beauties 

 on Manetti has been quite extensively 

 tried, but the results have not seemed 

 to be decisive either for or against this 

 method, and the gain, if any, was so 

 slight that all Beauties are now grown 

 on their own roots. 



So far as I know, none of our native 

 roses have ever been used as stocks 

 upon which to graft or bud roses for 

 forcing or garden use, and I presume 

 the probabilities are against securing 

 any good results, but the experiment 

 ought to be worth trying. We have 

 one or two native roses that are quite 

 vigorous in their growth, and they are 

 doubtless resistent to the evil effects 

 of the alkaline salts so generally pre- 

 valent in the soil. Probably nothing 

 but an actual test could determine how 

 well they would respond to winter 

 forcing, though the chances are that 

 they would prove rebellious. 



Dormant roses of all kinds are hard 

 for us to handle. They are slow in 

 making roots, and it requires careful 

 handling to keep the wood from shriv- 

 eling. Such roses as the Crimson 

 Rambler are always in evidence in the 

 stores at Easter time, but plants that 

 are really well done are always scarce, 

 and no grower can be absolutely cer- 

 tain of his results. 



Roses in the Garden. 



Our people as a rule are but just 

 beginning to show a proper apprecia- 

 tion of garden roses and shrubbery, 

 and within the last few years business 

 in these lines has largely increased. 



Owing to the peculiar climatic con- 

 ditions already outlined, the growing 

 of roses in the garden always presents 

 a great many problems, and it is a 

 difficult matter to get the average 

 householder to understand just what 

 is required in the way of care, so that 

 repeated failures have discouraged a 

 great many. Dormant roses shipped in 

 from the east generally arrived with 

 the roots badly dried, and a large per- 

 centage of them die. Reputable con- 

 cerns should, for their own sakes, use 

 more care in packing shipments for 

 the arid states so as to prevent this 

 drying out. Shipments are also made 

 by the itinerant peddlers, who care 

 nothing for the interests of their cus- 

 tomers, and the buyer is not entitled 

 to much sympathy when he finds his 

 investment a total loss. But such 

 transactions are an injury to the busi- 

 ness, for a man is loth to try again if 

 his first purchase proves a failure. 



Winter Severity. 



Roses which are hardy in regions 

 where the temperature goes very much 

 lower than it does in Denver, often 

 winter-kill with us, but it is not the 

 severe cold which kills them. A plant 

 suffering from drought will not endure 

 the same degree of cold that it would 



