I'm thinking its Powdery Mildew.....started them in a cold, garage many months ago....but out in the hot summer sun it is still there.....read that a baking soda and water mix will do the trick.....plants are about 4.5 ft tall, just started flower process....over 85% of leaves have the "mildew"...all but the top 6 ".....anyone have success with the baking soda/water spray?

first timer....gardening mom!