Honey berry plant concern
Our tundra honeybeery plant and to a lesser extent our other honey berry plant have these unhealthy looking black leaves. See picture. It is a new garden plot with hauled in black dirt and "rotted" manure. The other plants in the garden seem to be OK
My guess would be it is sooty mold associated with honeydew secreted by aphids. Do you have trees overhanging the honeyberries? If so, they might have had aphids earlier this year, and the honeydew, a sticky secretion, dropped onto these plants. The sweet honeydew is an ideal environment for sooty mold. Read here:
You can easily check this because sooty mold would wipe easily off.
If this is not the case, then perhaps this is a fungal infection such as a mildew.
In either case, there is nothing you can do at this point.