Question
I have little white spots on the blooms of my petunias. What causes this, and what should I do about it?

Answer
Janie,
Without more details I'll suggest some possible causes and you can decide if any of these fit.
Are they white spots on the flowers? If so, these are usually places where small drops of water fell and the flower tissue died.  Nothing to worry about.

Are the white spots on the leaves or the leaves and flowers?  Did anything get sprayed on the plant?  Fertilizer?  Windows cleaned near the plant? Lawn products applied near the plant?  If products such as cleaners or fertilizers are sprayed near the plant these can cause white spots.

Can you shake or scratch the white spots off? It could be whitefly, aphids or mealy bug - all insects that can be killed by insecticidal soap.

No matter what the cause, try clipping off the worst leaves/flowers and marking the foliage/flowers that have no white spots by using a "twist-um" like what comes with plastic bags, or a piece of yarn. Marking the foliage that isn't white spotted will allow you to monitor the plant and see if the damage is still going on. If not, you don't have to worry about it because the damage has stopped. If the damage continues, and none of the above seem to apply, let me know and we'll brainstorm further.

all the best,
C.L.