6 Ways To Reuse Old Potting Soil 1️⃣ Landscape hole filler or topper for current beds - Use old potting soil in the landscape to fill any holes on footpaths. It can also be used to top off existing flower and vegetable garden beds. ⁠ ⁠ 2️⃣ Starter soil for new beds - Are you installing new beds in your garden that will be used in spring for flowers or crops? Old potting soil makes a great base soil. In the spring, you will top it with new soil and add appropriate fertilizer.⁠ ⁠ 3️⃣ Compost heap