black spots after spray
Hi, I'm very new to growing roses and still learning a great deal. I have some rose bushes and now two roses trees all in pots. I sprayed them all yesterday morning with a combination of water, baking soda, and a tiny bit of soap. I originally sprayed my rose bushes after finding black spots. Yesterday I also sprayed my rose trees as one of them had aphids. This morning I found that both of my rose trees have little black spots on the under side of the leaves, only where I sprayed. Obviously I hurt them doing this, but not sure why? ? ? The rose bushes did just fine on multiple occasions with such treatment. Any thoughts?