Leaves on roses bushes are turning yellowish and spoty looking?

what is causing this?

Leaves on roses bushes are turning yellowish and spoty looking?
Most likely you have black spot. You can treat it with 1tsp baking soda, 1tsp horticulture oil, 1tsp insecticidal soap in 1 gallon of water. spray leaves top and bottom once a week. In the future make sure your roses are mulched well and water early in the morning and only at the base. Roses hate to get wet. Watering in the morning will give the leaves a chance to dry if they get wet. If your rose is already established (been there for a season) then you only need to water once a week at most.
Reply:Sounds like black spot, i think someone else already mentioned that. If you don't want to play chemist,ou can just to Home Depot and buy a product called Ortho RosePride and mix it to what the package indicates. Furthermore, it wouldn't hurt to fertilize your roses with Miracle Gro Rose food every 7-14 days. Good Luck!
Reply:It could be black spot. Or you plants are malnourished, give them a little bit of fertilize
Reply:Horse manure round the base of the Rose should do it.
Reply:The best time to water rose bushes is in the morning so the sun has time to evaporate the water or black spot will develop and the leaves will turn yellow and fall off.
Reply:Give them some miracle grow and water often.