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 ARE PERENNIAL HIBISCUS DEER RESISTANT? How do I prune once the flowers turn brown during summer? What shade loving plants besides hostas will tolerate dry, heavy clay soil? 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?