I JUST RECEIVED 3 LARGE, BEAUTIFUL BLUSHING BRIDE PLANTS. I LIVE IN NYC AND HAVE TO USE CONTAINERS. CAN I USE STANDARD MIRACLE-GRO POTTING SOIL? OR DO I NEED A DIFFERENT MIXTURE? SHOULD I USE A MIXTURE FOR TREES AND SHRUBS? I WANT TO MAINTAIN THE BEAUTIFUL CREAM COLOR OF THE FLOWERS! THANK YOU SO MUCH!