Sansevieria like to dry out completely between waterings. The most common mistake made with these plants is overwatering. Even if your plant is placed in ample bright indirect light, you won’t need to water it more than once every 10 days (at most) during the growing season. During the winter months or if the plant is in low light, it can need watering as infrequently as once a month. Regardless of its placement though, make sure that you are letting your Sansevieria's soil thoroughly dry between waterings. Sansevieria are susceptible to root rot, so it’s very important that you do not water the plant if you detect any moisture in the soil.