Do water plant wet those lower leaves. And what name plant? I never trim leaves. What age plant stem in photo if flora-cane that problem.

We get a lot of evening rain, the spots are on my Triple Crown and Apaches. The stem is this years growth.

It's also on your canes..notice the dark spots. Probably something fungal...maybe cercospora leaf spot. I usually just search google for something like "blackberry plant brown spots" and then look through the "Images" section. You will usually find a picture that will help you identify the type of plant disease.

I don't know if it is worth worrying about now..the leaves are going to fall soon and the plant will go dormant. You may want to remove the infected leaves after they fall. That will help keep the fungus from spreading next year. You may also want to do a lime-sulfur spray before the plant leafs out next spring.

There are additional sprays you can use after lime-sulfur but I have found that Triple Crown and most of the eastern blackberry varieties usually push through minor leaf fungus infections fine without the additional sprays.