Hi, I am new here but I need your help. I bought my first rose bush and planted it in a pot. I live in an apartment so planting in the ground was not an option. I planted it with potting soil, in an 18 inch wide pot that is very deep and has a water trap on the bottom. I placed rose food 1 inch under the top soil, not too close to the base of the plant. I pruned the dead blossoms off last week. It gets about 75 % sun per day. Yesterday the leaves started getting dry, crunchy, and brittle starting from the tips of the leaf to the stem. Please see photo. Can anyone tell me what is going on with my beautiful rose bush? I greatly appreciate any help. Thank you.