How to know if Grafting is Successful?

last 3 days ago I had done my grafting project by grafting a tea rose and a Poland rose. We put it on a side where it's shady and the sun seldom shines there. So It went perfectly fine until yesterday I noticed that it started to have horizontal lines, it was still hard and not decaying as i touched it but I'm pretty sure that it's dying. I did four and so far only 2 has started to have visible horizontal lines, so I don't want the other two to be like that so what should I do? Where Did I go wrong? Am Should I put it in a sunny area?Please Help! I'm really desperate!