I have 3 hops plants, this is about year 3 or 4 for them, 3 Cascade and 1 Nugget. They are all growing nicely, but about a week ago I noticed the leaves on the bottoms turning brown. Now, more leaves farther up a browning and parts are just gone. I don't see any insects, mildew or fungus on them. I think the same thing happened last year. We've been getting decent rain here, and usually give them each a pile of compost/manure early in the spring and I gave them a dose of organic fertilizer about 2 weeks ago. I'll attach some pics for reference.