So after a couple years, what the best thing to do? Dig them out, cut the rhizomes back and replant a small rhizome?
The planters I've got are pretty large, each one took an entire 64-quart bag of potting soil, with room to spare. My wife and I are stuck in a condo for at least a few more years, hoping that the planters can work for a while yet.
I have four varieties, in four half-whiskey bbls. After three years, they all become quite root bound. What we did a few months ago was dump all barrels (1 at a time) onto a tarp. cut out as many rhizomes as we could, then cut the crown in half, and replanted. My fuggles are 4 feet tall at this point. and the others are just barely behind that. Last year, I got over ten pounds of dried hops. Or at least what I THOUGHT were dried. They became moldy, and I had to throw them out. This fall, I will dry them well past when "I think" they are dry enough. Maybe do that weight process to make sure.