soon as one of these troubles occurs, either destroy the plant and get a 

 clean one in its place or isolate the sick plant. Mealybugs may be killed 

 one at a time by pricking with a toothpick, but this is a long, tedious 

 process requiring several weeks or even months to get a plant entirely 

 clean. By far the easiest method for controlling mealybugs on African 

 violets is to obtain clean plants and keep them clean by never letting 

 them come in contact with other plants that are infested with mealybug. 



kV#a 



Fig. lOd — A normal African violet (center) compared with an in- 

 jured plant (left) watered with cold water. On the right 

 is a plant infested with mites 



The cyclamen mite cannot be seen with the naked eye but the trouble 

 if causes is easily recognized. The basal portion of the upper surface of 

 the leaves, near their junction with the petioles, first develops an unusual 

 fuzziness. The leaves, especially the new and tender ones, begin to curl 

 and, in severe cases, the leaves become so deformed and crowded that 

 flower stems cannot get through them. The mite usually comes in on 

 new plants, hence a good argument for quarantining until they have 

 proved to be clean. The cyclamen mite is spread primarily by contact 

 or handling. There is no satisfactory method for controlling cyclamen 

 mite under home conditions, so plants showing cyclamen mite injury 

 should be discarded as soon as discovered. 



Leaf Spot 



Although not giving appreciable trouble to the growers in this ex- 

 periment, leaf spot is a rather common trouble on African violet. It ap- 

 pears as yellowish-white spots or blotches on the leaves and may cover 

 almost the entire plant in severe cases. Contrary to popular belief, this 

 trouble is not caused by water on the leaves. Workers at the Ohio Ex- 

 periment Station have produced the trouble by watering plants with 

 cold water. They have been unable to produce leaf spot on African vio- 

 let when watering with warm water even when the leaves were watered. 

 This trouble may be avoided by watering with lukewarm water. 



Suggested summer care 



Since African violets are very tender, it is not advisable to place 

 them out of doors during the summer. Plants may be flowered the year 

 around or they may be rested through the summer by allowing them to 

 run slightly drier than usual. Continual blooming for from 12 to 18 

 months was not detrimental to plants in this experiment. Windows with 



Eighteen 



