About 90% of the leaves on this shrub, which I planted about three months ago, have this kind of spotting. I have examined it under a powerful magnifier and there is no obvious sign of chewing insect damage, so I suspect some kind of fungal leaf spot. The most severely affected leaves are closest to the base of the plant and the unaffected ones are at the tips of the growth. Any help would be appreciated.
My guess is probably fungal, maybe bacterial, but mostly from moisture hanging out too long. If it is just at the bottom, then try trimming a few of the bottom laterals, and then 1 or two branches in the middle (not a main one). This will help with air flow. Do no more than a few inches of removal, and only about 1/5 or so this late in the season. (unless it flowers, then I advise trimming based on bloom formation on old or new growth). K-State zone 5a-b link to trimming
