How to reuse old soil. There are a few additional steps you can take to make sure your mix is good:⠀ ⠀ ➡️You could add some slow release fertilizer. Or not, if you fertilize your plants when watering⠀ ➡️If you want to be more scientific, you can also check the PH after mixing to make sure it's in the right range, between 5.5 and 6.5 for most houseplants. Why is PH important? If it's not in the optimal range, plants will have a hard time getting nutrients. So even though your soil might be full o