Question
I have one AV here at work.  It is in a north-facing window and has been thriving until recently.  The leaves are still a beautiful green and it blooms almost constantly.  I the last month,it has developed white spots on the blooms only.  I am wondering what may be happening and if there is anything I can do for the plant.  I water it with tap water.  It blooms in spite of the fact that I have not fertilized it.  I have several violets at home, which is where this place came from.  They are all doing well and have no spots.  They are in an east-facing window and are fertilized with Schultz AV fertilizer with each watering.

Answer
White spots may be one of three things.

Powder mildew: Most often on foliage only.  Paint with a solution of 1 part milk, 9 parts water.  

Foliar Mealy Bug: Most often on foliage only.  Scrape with Q-Tip dipped in Alcohol.

When it involves the flower only, I believe this to be a fungus called Botrytis.  The only "cure" for this is to pinch off all affected flowers and allow it to flower again to see if it is again infected.

Botrytis is a fungus with spores which fly through the air that will infect your entire collection if it is in the same room, or reinfect this plant.

Removal of flowers may help.  Otherwise you would need to buy and spray Benomyl.  Personally if only one plant is infected the cost of the fungicide is more than that of a new plant.  I would test its next bloom cycle or put this plant in the garbage and buy another.

Good luck!

Nancy
I advise you to take off all flowers, keep it away from other African violets and see if the next round of blooms come in with this.