I have used luster dust before on my fondant cakes but I have never used petal dust, I'm getting ready to add some color to gumpaste flowers do you paint the petal dust on or just dust them?

depends on the effect you want. Dust adds soft color, 'paint' is a much stronger color. I usually prefer the softness of dusts.

You can make the color softer by blending the plain dust with a small portion of cornstarch

I agree. If you paint it, you'll get very strong colors and probably some streaking. If you dust it you get a nice soft color. There is a picture of a really UGLY cake in my albumI did where some of it was painted in petal dust. Easy to spot. Would never do that again.

http://www.cakecentral.com/modules.php?name=gallery&file=displayimage&pid=67344t.

I wouldn't call it ugly - I think it looks fabulous! The variations in colour look like stained glass - great job!

fairytale if I might say....if that cake were ugly it wouldn't of been 50 peoples favs Very pretty cake!!!

You really are very hard on yourself! I think your work is just lovely.