Anatomy of a planter: use a lightweight filler on the bottom, followed by a layer of landscape fabric. Next, use quality soil. Loose, peat-based potting soil is the standard for containers--it's light and well-aerated, and it drains perfectly. Allow drainage: an outdoor planter must have a drain hole. If not, create one with an appropriate drill but. A filter pad at the bottom of the pot will keep soil from escaping. Top it all with mulch, which will help reduce water loss and prevent soil from