Water

Don’t allow your cannabis plants to sit in their own runoff unless its living soil and you are only watering and feeding teas but not using salt-based nutrients. We tend to feed cannabis heavily for production. That makes for some concentrated run off. Plants elevated above their run off are less likely to have issues cause by accumulated salts which remain at the bottom of the pot. when the run off evaporates into the atmosphere or is reabsorbed by the plant. Those accumulated salts can cause hydrophobic soil issues, where the soil quote literally repels water. The issue is resolve by simply elevating the plant above the runoff collection tray. This can be done with recycled containers like shallow food tubs turned upsode down with a couple of small tabs cut into the rim of each tub to allow water to flow under the tub rather than be displace by it. They make pot elevators but they are costly and quote easily made from many repurposed items. At the end of your grow, note the accumulation of salts along the edge of your tray. Those would have built up in the bottom of your pots, and can negatively impact your grow.