Azalea diseases ?
Last year my azalea's leaves all turned brown. The vigorous new shoots around the base of the plant died. This year I applied Bayer Tree & Shrub Insect Control Concentrate (http://www.bayeradvanced.com/product/Tree-Shrub-Insect-Control/concentrate.html) with the hope the problem was caused by insects. Now the same problem is happening again. But this time I'm hopefully catching it right as it starts and can still do something about it. I've a link to photos of the leaves below. It looks like three different kinds of diseases are happening at the same time. The azelea is a few feet from a lilac which has powdery mildew. I've been watering the azeala was applying Miracle Grow about every other week. Thank you for any suggestions you might have on how to control this.
Here is a link that might be useful: photos of leafs