Hydrangeas under attack

Bill,
As you can see, my hydrangeas have a disease.  First let me give you a little history, then you can diagnose.

These are some of the continuous blooming hydrangeas. As always, Glenna and I wait around until shrubs get marked down to fifty percent off, then buy. We really like these. They bloom on old and new wood and so tend to giving repeating flushes of flowers through the year. In fact, they are putting out flower buds all over right now.

However, about two months ago, one plant began looking yellow and weak on one side. The purple spots appeared and it has spread throughout the others also. There are two new plants I put in later this year that also have spots, like these three year established ones do.

I looked online for information, and it seems that leaf spot is ugly, but rarely fatal. At least that is the diagnosis I found. How can I tell the exact disease without a lab test? I will be cleaning up around the plants in the fall, discarding the leaves and old mulch. Then watching next summer for any return, I will decide if I need a fungicide or not. In general, I do not like to use chemicals, but I am not adamant if the situation calls for it.

Meanwhile, that corner of the yard had been my pride and joy. Lush, watered by run off rain, interesting plants. But there is a mar on the beauty now. It may be that the drought of this last summer weakened the plants. There are hosta plants nearby with browned leaf edges from lack of water. And, of course, we did not help the situation because when we watered, we did so from overhead, spreading the spot from leaf to leaf.

I suppose this is all part of the fallen nature we have made of God's creation. Also, I suppose that perfection in a garden is a contrived artificial thing, with lush plants all arranged in a perfect order, looking like symmetrically placed plastic and silk foliage. A little trouble in the garden makes it look real.

Hope your plants are looking good.
Bob