I planted candy stripe subulata phlox last year, AND this year on the west side of a very tall oak tree. I have created a raised bed around it and thought this would be the perfect plant to fill in the crevices. I have put in good dirt, mulched, planted my phlox, used Miracle Grow quick start, watered frequently and they are dying....again. I don't get it, they are supposed to LIKE the sun and they die. I did buy them in large pots from a good local greenhouse and divided them into 3x3 sections so they would spread...perhaps that's the issue? I am frustrated that my phlox won't grow. Does anyone have any suggestions as to what this newbie is doing wrong?