The time frame for watering bamboo plants depends on whether they are outdoor or indoor plants. If bamboo is planted outdoors in a temperate or mild climate, then it is important to water it at least twice per week.
When the temperature is hot or windy, bamboo may require daily watering. The watering requirements of bamboo can also depend on the size of the plant and whether it is transplanted. These bamboo plants require more watering until they reach an optimum height. For example, if the plant is larger than a 5-gallon pot size, it requires more than 1 gallon of water. After the plant reaches its optimum height, bamboo does not need heavy watering.
If the bamboo is kept as an ornamental indoor plant in a vase, the owner should ensure the vase contains pebbles and 1 to 2 inches of distilled or bottled water. The reason for this is that tap water contains chlorine that can affect bamboo. The water should be changed on a weekly basis.