I would use a good potting soil for a hanging basket rather than trying to mix up my own. You need a soil mix that is light weight but holds moisture. The bag of potting soil should not feel wet and heavy when you pick it up. If fertilizer is not already added to the potting soil (it will say so on the bag if it contains fertilizer) then be sure to add a slow release plant food like Osmocote to your potting mix before adding the plants. Keep growing, Marianne Binetti