That's interesting. I have roses in my garden, They form a long border down one side. Last summer, a young friend who was helping me with the garden emptied the content of an old compost bin on the roses bed - they loved it and produced two more sets of flowers.
I share a long hedge with several trees with my neighbours. In October, one neighbour had her tree trimmed by a third to let them in more light. It was slightly shocking to come home to a denuded tree and so much more sky, but it will be good for the garden in the summer to have more sun.
All right. This is all you need for roses.