A rattlesnake calathea plant generally prefers evenly moist soil, but it should not remain waterlogged. Check the soil regularly and water when the top portion begins to feel slightly dry. During warmer periods, the plant may need watering more frequently, while cooler conditions can reduce its water needs. Use a container with drainage holes so excess water can escape. If the leaves develop brown edges, inconsistent watering, dry air, or water quality may be contributing factors. Adjust your watering routine based on the plant's environment rather than following a strict schedule.