As there is no standard or fixed schedule for this one, watering cannabis will need close attention especially in seedlings.
Naturally, cannabis prefers a lot of water but they also need to be let dried off at least a day or two before next watering as their roots also need a lot of oxygen as well. Most commonly used method to check if it’s the right time to water is to stick your finger about 1 inch into the topsoil, if it's dry you are good to go. Also be careful not to let runoff excess water sit under the container.
One of the most common mistakes is overwatering, which can be triggered by too much or too frequent watering or both.
Sometimes overwatering might not show signs of illness right away but in the middle or late stages of the plant due to drowning roots or long periods of accumulated wetness in the rootzone. This results in some nutrition uptake problems such as calcium and magnesium deficiency, which commonly followed by phosphorus deficiency or even worse, a root rotting as overwatering is not just like drowning the roots but also allowing anaerobic bacteria, pathogens or pests to grow.
