Help - Azaela leaves turning yellow
My Azaela's were so good this spring with full blooms of white and pink. Now that the season is over for them, there are just green. But lately some of the leaves started turning yellow and reddish to be more specific with some brown/black spots on them.
Any ideas what is happening to these? I just water them once every 2 days to keep them moist. I have prepared the soil of my flower bed like 3 weeks back adding humus & manure and Miracle-Go Garden Soil mix. Apart that i am not feeding them any fertilizer or anything. They get good sun for most of the day and stay in shade by late afternoon.
Yesterday when i was spraying my roses with Ortho for blackspot, i did spray the azalea's too. Did i do anything wrong?
Here are the pictures: