OUTDOOR ROSE GROWING 



good remedy is grape dust, which can be obtained 

 in any seed store or from any nurseryman with 

 directions for use. Another remedy is a solution of 

 sulphide of potassium, one-quarter of an ounce to a 

 gallon of water, to which add one and one-half 

 ounces of common soft soap. The soap should be 

 boiled before being added to the solution. This is 

 the cure we prefer. 



Black spot is another disease which sometimes 

 comes towards the end of the summer. We have 

 experienced it mostly in potted greenhouse plants 

 and we advise against planting roses from pots, as 

 each time we have done so black spot has resulted. 

 If we plant only dormant field-grown stock we 

 do not have this disease. Dr. Huey concurs in 

 this opinion and, as a cure, advocates picking off 

 such leaves as are affected as soon as they appear. 

 Last year we used a formaldehyde solution with 

 fair success, but black spot is most difficult to 

 eradicate. 



The " American Florist," in its issue of June 14, 

 1914, has a very interesting article on black spot 

 treatment, taken from publications of the National 

 Rose Society of England. The main point in the 

 article is that black spot is a fungous disease which 

 invades the living tissues of the plant and there 

 reproduces itself by means of spores on the leaves. 



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