I think you may have several issues
1.) Mites / small pests (as suggested)
2.) Possible over-watering. I know this seems counter-intuitive considering how everyone talks about how much water hops need, but when growing in a container the soil retains moisture for a far greater amount of time. Allow your soil to dry out before watering again. I live in Colorado, which is fairly arid, and I water my container hops once every two to three days, as an example.
3.) Drainage...This goes along with # 2 in that you have a very large trash can there and I can imagine your roots becoming waterlogged if the soil isnt loamy enough. Some have suggested mixing gravel in with the soil to increase drainage. I prefer peat moss. The best way to judge your own soil would be to grab a clump of it. You shouldn't be able to form it into a ball and have it keep its shape...the soil should be loose, dry, and healthy. ALSO, I assume you drilled some holes in the bottom of that baby?
4.) Fertilizer. Be careful using Miracle-Gro with your hops. Synthetic ammonium phosphate fertilizers (like Miracle-Gro) can acidify your soil beyond the proper PH range, causing the roots to suffer. I like to recommend this fertilizer. It's light, safe and organic, and when paired with proper soil preparation, only needs 2 to 3 applications over the course of the season.
5.) Your 5th and final issue is that you only have one beer. I like to go through a six-pack when working with my hops.