I have second year Cascades growing vigorously. However some of the lower leaves are starting to shrivel and brown on the edges as you can see in the picture. Is this a nutrient deficiency? Is there anything I should do to remedy this? The plants seem otherwise healthy. Thanks.
I had the same thing happen both last year and this year. I never really investigated this too much because my plants were destroyed by bugs last year so this was the least of my worries. I’d be interested to hear what everyone else recommends. I have seen a few holes and small bugs, but the full Japanese beetle swarm hasn’t reared up yet this year.
I’ve had a similar problem with my vegetable garden last year. Someone told me it may be a nitrogen definciency. I used a slow release fertilizer with a fairly high nitrogen content. The plants survived without much further damage, but i can’t be certain the fertilizer saved them. May not be the answer, but it sure can’t hurt! Good luck. 
I did add some organic fertilizer recently, but it’s pretty slow release and not particularly heavy on the Nitrogen. Guess I’ll try a bit of bloodmeal and see if that makes a difference.
it doesn’t appear to be browning at the tips of the leaves as a deficiencey would. looks like something is being sprayed on the leaves. is it possible something is peeing on your plants or something splashing from nearby.
Thanks for the replies so far. We’ll get this figured out.
The area is fenced off so don’t think anything is peeing on the leaves. I started the season by adding a bunch of steer manure compost but haven’t fertilized yet. I’ve added some organic material from cleaning the bottom of my pond out. The only thing I’ve sprayed is some Safer Insect Killing Soap http://www.amazon.com/gp/product/B00192 … UTF8&psc=1. I think the leaves were like this before spraying, but don’t recall for sure.
The active ingredient in the Safer soap is potassium salts of fatty acids 49.52%. Would that do this? I sprayed my other veggies and roses with it too and none showed this same effect.
some of the leaves also have this frosty white tip appearance.
I know this isn’t a diagnosis, but some reference material for hop growing:
http://ipm.wsu.edu/field/pdf/HopHandbook2010.pdf