We are renters and we are trying to care for about 14 rose bushes. Neither of us have prior experience with these bushy beauties, but we are learning as we go. I have been watering then twice weekly (about 3 gallons each) for about 2 months now. We have recently added compost to the soil, and I just bought some organic rose fertilizer. We are trying to do this organically.
One of the rose bushes has developed these symmetrical brown spots between the leaf veins, and the leaves that are browning are wilting slightly. It has not dropped any leaves yet.
I have noticed a couple of leaves on two other bushes doing the same thing. I can post links to pictures tomorrow. In the mean time, any idea what we might be doing wrong?