This is my first time posting and have run into a little problem with designing my perennial garden. I decided to redo an old overgrown garden and plant some perennials. I bought some knockout roses, tickeseed, may night salvia, walkers low catmint, peppermint stick spirea, lambs ear and sedge evergold grass. This garden is on a slight hill with the back being at the top. I planted 5 knockout roses along the back to give it a border and am confused on how I should arrange and plant the rest of my perennials. I attached a picture of the garden and a drawing of the area with my plants. Any ideas on how to arrange them to make them look great? Thanks so much!