Well, this is my lesson in patience and a lesson for those that can't see below the ground. I planted 3 kinds of hops this summer Cascade, Nugget and Centennial. The Cascade and Nugget 'blew up' so to speak and shot up tall, and I even harvested 2 wet pounds of cones, between the two (~1.5 cascade & 0.5 nug).
I had two 'starts' for the Centennial one shot up to about 3.5 feet and the other 1 foot. Then they just stalled and didn't really grow much for the rest of the season. They bushed out a bit, and in the end produced 2 cones, total.
BUT, there are a lot of threads and links talking about how first years spend most of their time growing the root system (rhizome), etc., etc. but as a newbie, it is hard to believe what you don't see (just like having faith).
I believe there were several reason why the Centennials just grew and 'stopped' and here is the list: 1) the other two plants grew in a non-grassy area, with no competition with other plants, well drained soil bed, and the Centennials I put right in the tight-root-matrix grass area. 2)The landlord hits the grass with broad leaf herbicide several times a year (not at all where the other plants grew). 3) We had an unusually hot and dry summer here in WI, where I have read (and observed) Cascades and Nugget don't seem to mind, it seems Centennials are a bit touchier. 4) There was a field mouse trench within inches of the Centennial plant base/root area (not at all with the other two plants). 5) There was minor wind damage, Japanese beetle attack, soil drainage differences between where the Centennials were and the other two plants.
But in the end, I decided to move the Centennials from their less fortuitous location to a similar location as the other plants, and so I was prepared to dig up the Centennials. Here are the pictures and all I can say is WOW! I do not have any experience with rhizomes, since all of my plants were 'starts' that started about 0.5 centimeter wide shoots maybe 3-6 inches tall with a tiny little root system in a clump of dirt. Despite all of the setbacks and perceived hardships the Centennials went up against, this seems like a nice large root system they have established. I did my best not to break and damage too much as I was digging it up, but I do know that even being as careful as I was, there was another medium/large root that went deeper than I had dug. The dimensions of my hole was 10-12 inches around but 6-8 inches deep, and you can see from the pictures I just kept uncovering more and more rhizome.
So for all you out there that planted first years, and didn't get much or see much and are down on your plant, just WAIT! There is probably a huge root system just below the surface. Lookey here and see.
p.s. and YES that is my 2 year old son's dump truck that I rented (for a reasonable price) to transplant, the plant.