86 GREENHOUSE MANAGEMENT. 



conditions favorable to their propagation and growth. 

 Much can be done to hold them in check if the 

 decayed leaves are frequently removed, and the germs 

 destroyed. 



With healthy plants to start with, and with proper 

 care in watering and ventilating, the danger of the 

 appearance of the various violet diseases will be greatly 

 reduced, but if any of the plants show traces of any 

 disease, the injured leaves should be pulled off and 

 burned. The surface of the soil should also be occa- 

 sionally stirred and all litter removed. 



The violet is troubled by few insects, the most trou- 

 blesome being the aphis and red spider ; frequent fumiga- 

 tion for the former, and syringing for the latter, should 

 hold them in check. 



VARIETIES. 



Until recently the Marie Louise was more largely 

 grown than all other varieties put together. It is of a 

 rich, dark blue, with a whitish center. The flowers are 

 large, firm, and quite fragrant. When healthy, it 

 is vigorous and quite floriferous, but for several years 

 many florists have been unable to grow it successfully, 

 owing to its liability to the attack of some of the various 

 diseases of the violet. 



Lady Hume Campbell has with many growers super- 

 seded the above kind. The plants are strong, compact, 

 and quite free from disease. The flowers are large, 

 double, extremely fragrant, with long stems and of a 

 light blue color. 



The Farquhar is a new sort that has been less thor- 

 oughly tested, but the very highest claims are made for 

 it so far as health, vigor and freedom of bloom, and the 

 form, color and fragrance of the flowers are concerned. 



Swanley White is still the best of its color, but is 

 little grown. 



