May 3, 1919 



II HT1 C U L T UKE 



I'.'L 



Although it is generally believed 

 that magnesium in excess is the mosl 

 poisonous ol" all the plain nutrients or 

 fertilizers, Tonk, as early as 1889, 

 recommended a manure for roses con 

 taining sulphate of magnesium with, 

 however, an excess ol" lime. Here the 

 matter rested for twenty years. In 

 1909, Truffant noted the large propor- 

 tion of magnesium found in the analy- 

 sis of roses, and stated that soils de- 

 ficient in this element produced bul a 

 weak growth of roses, but that the 

 addition of magnesium salts brought 

 about a marked increase of vigor and 

 growth. The following year at the 

 International Rose Conference, in 

 • Paris, the particular value of mag- 

 nesium for roses was one of the sub- 

 jects for discussion. It was declared 

 to be indispensable and it was stated 

 that it should always lie given in the 

 form of sulphate in doses of about five 

 ounces to the square yard. 



As the result of recent experiments 

 and the experience of at least one 

 practical rose grower of national rep- 

 utation, it is believed that the follow- 

 ing practice is correct: Attention 

 should be called to the fact that all 

 roses do not react alike, and some 

 varieties not yet tested may not re- 

 spond satisfactorily or may even be 

 slightly injured by the magnesium. 

 One should, therefore, proceed cau- 

 tiously. If plants are to be wateied 

 with a solution, use nitrate of mag- 

 nesium at the rate of one ounce to the 

 gallon. This may be used once a 

 week through the season, but if any ill 

 effects are noted, the application 

 should be discontinued. If the mag- 

 nesium is to be applied dry, it is bet- 

 ter to use finely powdered commercial 

 carbonate of magnesium which con- 

 tains a certain amount of lime. This 

 should be applied at the rate of one- 

 third of a pound to the square yard. 

 No immediate effect will be noticed 

 ft om the application, but, later, in- 

 creased sturdiness and consequent 

 richness of foliage and blossom should 

 result. 



Insects. 

 Half starved and otherwise ne- 

 glected roses are quite susceptible to 

 insect attacks, which, however, is not 

 the case if the plants are properly 

 cared for. The most serious insect 

 enemy of the rose is probably the 

 green By, well known to all who have 

 grown roses. It is a small, green 

 plant-louse, or aphid, about one-eighth 

 of an inch in length when full-grown 

 and usually wingless. The body is 

 oval and soft and secretes a sweet 

 fluid of which ants are particularly 

 fond. The presence of ants on rose 

 bushes is good evidence that the 



aphids are at work. The latter usual- 

 ly work on the young shoots, sucking 

 the juices with their long, slender 

 beaks, and if unmolested quickly de- 

 stroy the vigor and vitality of the rose 

 plant. The most effective agent witli 

 which to combat the aphid is tobacco 

 smoke, but its use out of doors is ob- 

 viously connected with serious difficul- 

 ties. In its place, however, a solution 

 made from tobacco stems and whale- 

 oil soap will he found effective. To 

 make this solution one pound of to- 

 bacco stems should be soaked in a 

 gallon of water over night, after which 

 one ounce of whale-oil soap which has 

 first been dissolved in a small quantity 

 of hot water, should be added (it will 

 require three or four hours for the 

 soap to thoroughly dissolve). The so- 

 lution so prepared should be thorough- 

 ly stirred before using and may be 

 applied either with a sprayer or with 

 a whisk broom. This quantity is suf- 

 ficient for about twenty-five plants. 

 Where a sufficient water pressure is 

 available the green fly may further 

 be kept in check by vigorously spray- 

 ing the plants from time to time, as 

 required. 



Another troublesome pest of out- 

 door roses is the rose hopper, or 

 thrips. This insect is small, yellowish 

 white, about three-twentieths of an 

 inch long, and provided with a pair of 

 transparent wings. It preys upon the 

 leaves, working especially on the un- 

 der side, causing the foliage to as- 

 sume a sickly yellowish appearance. 

 The control of this insect is more dif- 

 ficult because of its active jumping 

 and flying habits. Spraying the plants 

 with water, so as to wet the under 

 side of the leaves, and subsequently 

 dusting them with powdered hellabore 

 usually effects a sufficient control. 



Several kinds of caterpillars prey 

 upon the rose, sometimes causing con- 

 siderable injury. All of them envelop 

 themselves in the leaves or burrow in 

 the flower buds. Powdered hellebore 

 sprinkled over the plants prevents to 

 a considerable extent the movements 

 of the larvae, but removal is best 

 accomplished by actually picking them 

 from the plants. 



Fungous Diseases. 

 The mildew is perhaps the common- 

 est disease of the rose Some varie- 

 ties are seldom attacked and certain 

 locations are muc'fl more subject to it 

 than others. The disease generally 

 makes its appearance in the autumn, 

 when the nights begin to grow cool. 

 At this season, however, it works but 

 littlo harm, as the plants have made 

 their growth and the wood is nearly or 

 quite ripened. A mixture of equal 



parts of quick lime and sulphur, ap- 

 plied when the dew is on the plants, 

 will usually prevent mildew. The fol- 

 lowing solution has been used success- 

 fully: one ounce of copper carbonate, 

 one pint of ammonia, and ten gallons 

 ol water. Plants should he sprayed 

 with this mixture once a week, using 

 a nozzle giving a fine spray. 



Winter Protection. 



The work of protecting roses against 

 the severe cold of the winter should 

 be done by .November 20. The earth 

 should be heaped up around each plant 

 to a depth of from two to three inches 

 in order to provide drainage away 

 from the center of the plant, and from 

 four to six inches of straw manure 

 should be placed over the entire sur- 

 face of the bed. This treatment will 

 protect any of the varieties previously 

 mentioned, except the tree, or stand- 

 ard roses. These are budded at the 

 crown and unless wrapped with hay or 

 straw, freeze very easily. 



Pruning. 



One of the most important consider- 

 ations in rose culture is that of prun- 

 ing. Xo directions can be given which 

 will be sufficiently explicit to enable 

 one to know just what to do in each 

 individual case: practical experience 

 alone can furnish this information. 

 But. the general principles that should 

 be observed in pruning can be readily 

 stated. As regards tools, a pair of 

 good shears and a pruning knife with 

 hooked blade are desirable. The work 

 can be more quickly and easily done 

 with the former, but where a very 

 smooth cut is to be made, the pruning 

 knife is preferable — also because it is 

 less likely to bruise the bark. 



All pruning should be done while 

 the plants are dormant. The chief ob- 

 jects to be held in view- in pruning 

 roses are: the production of a sym- 

 metrica] plant, and the promotion of 

 flower bud formation. To secure these 

 results plants of delicate habit and 

 weak growth should be severely 

 pruned. Vigorous growers, on the 

 other hand, should have the shoots 

 only moderately shortened, but the 

 branches well thinned out. In all cases 

 the cut should be straight across the 

 stem in order to expose a minimum 

 amount of wounded surface, and care 

 should be taken that the top bud 

 Which remains points outward. Climb- 

 ing roses require no pruning beyond 

 cutting out the very old and dead wood 

 and shortening thF laterals, except the 

 trimming which may be necessary to 

 make the plants conform in shape tc a 

 particular arbor or trellis. The ten- 

 dency seems to have been towards 

 over pruning. 



