Elegant self-watering glass bulb - perfect for thirsty potted plants. With the self-watering bulb, the plant determines how much water it needs to drink. The soil is moistened as the soil becomes dry. Fill with water and introduce directly into the soil. Really thirsty plants may need water before the self-watering system is emptied, especially in hot weather.-Wash by hand*Note: Avoid placing the self-watering bulb in direct sunlight. The sun's rays can make the bulb very hot.