It looks like a lack of nutes. I doubt your plant is going well in that pot. Is it ceramic? Black absorbs heat and will be frying the crapper out of the sides of your pot. It will be dry a few inches in around the edges and preventing proper uptake of nutes. If you can mate you should just plant it in the ground. It will go off. Or you could just wrap the pot in foil to deflect the heat. Works a treat for meat on a webber. What kind of feeding do you give it? Both water and nutes. Hops are nitrogen hungry so if you are not already, get yourself some seasol and powerfeed to fertilise. The seasol will help repair the roots and make your rhizome stronger/larger. It will also then improve uptake of other nutes. Powerfeed will give it an all round feed of nitrogen phosphorus and potassium. Brown spots are normally a lack of phosphorus and or potassium. The yellowing is notrogen deficiency. Work out the dosage so you can give them a feed every 3-4 days instead of fortnightly. Having access to more frequently over massive dosing is more efficient. Did you add any organic material into the pot? Horse poo or compost or both? If not you can add a ring of poo around the rim of your pot, and fill in the rest with good soil or compost. Then get some sort of straw mulch on top. You can try and make up a spray bottle with nutrients in it, and apply to the leaves in the evening. They should absorb enough to correct some of the defficency. Hope that helps.