I've never grew hops but I have had a garden and when Its dry and hot and I keep forgetting to water the plants the leaves get kinda orangish to yellow.
That might be the problem, they are in planters. I usually try to give them 1/2 gallon of water every two days, but might forget sometimes. Is this an average amount to add? or should I use more. The temperature here has been in the 80's, today it reached 90F.
I would check the back of the leaves for little black spots that move and what looks like little webs. If so it's spider mites. I get them every year if I don't keep up with seven spray.