Considering this, how do you treat root rot on ZZ?Once the ZZ is out of the container, check for signs of rot in the roots and rhizomes If you can't get a good look, use your fingers or gently rinse the base of the plant under water to remove as much of the soil as possible Then take a closer look at the roots and rhizomes to assess the damage Healthy roots and rhizomes are crisp and white Overwatering can cause the rhizomes to rot and deprives them of the oxygen they need Cut back on ZZ plant watering in winter months , when the plant goes through a period of dormancy Advertisement Zz rhizome rot