Sharon, It's not powdery mildew, it looks like snow. I think you have mealy bugs. Once they get well established they are almost impossible to get rid of. Dabbing the blobs with alcohol using a q Tip will kill them. But there are eggs lingering and youngsters crawling about, so after the dabbing of those you can see I'd spray the plant with a strong stream of water. Let it dry and then spray it with insecticidal soap. You will have to repeat the insecticidal soap treatment every 7 to 10 days for several weeks. Good Luck and Happy Yardening, Nancy.