Spotted Boysenberry Vines = Septoria Leaf Spot

The Nanaberries are beginning to ripen. Yesterday we all had a choice first berry of the season. Just in time, too, since I opened the last jar of jam this week.

This year brings a new issue with the berries: Spotted leaves. All over last year's canes. The way we were instructed to grow these from Cyrus' grandfather when he gave us some rootings was to clip away the previous years growth and train the new canes up in the fall. The previous year's canes then produce fruit the following summer. I have to admit we were tardy on both clipping back and training up, which I see we may be paying for now with a fungus or bacterial problem. All our late season rain (yay! not complaining about rain in California I swear!) may have aided in this as well.

Some of the canes have completely died back, shriveled baby fruit and all.

The flowers were completely fine this spring, there are a few remaining and they are perfect little spotless flowers.

The spots can be found on the leaves AND the canes. Here is a front and back and sun view of an affected leaf.

I did a bit of searching around and am wondering if it could be Septoria Leaf Spot but I'm afraid I just don't know enough about it.

Anyone have any ideas?

I'm considering pruning all the canes back to the ground after this season and spraying sulfur all over everything.

UPDATE: Looks as if I was on the right track! Shauna over at Chronicles of a Pacific Northwest Gardener gave me this link on Septoria and the photos are dead on. Thanks Shauna!