Question WHEN IS THE BEST TIME TO PLANT CREEPING PHLOX? Answer Creeping phlox is a tough plant! You can plant it either spring or fall. If you plant it now, you will be able to enjoy it early spring when it flowers. Tags: CareDesignFAQProjects Related Questions Why is the plant turning black? I was given a lovely Vanilla Strawberry Hydrangea and the leaves are turning yellow. I read that watering on top can make that happen. I checked the soil and it’s good and have mixed in some food. What am I doing wrong? HOW MANY FEET AWAY FROM OUR HOUSE SHOULD WE PLANT THE ENDLESS SUMMER HYDRANGEAS? Why do my blooms look burnt?