Plants are living beings and prefer regular care, but frequent or lengthy absences need not stop you from filling your home with greenery. Some house plants, such as cacti and succulents, can literally go for months without water and should be perfect for even frequent travelers. By using watering systems such as wicks, capillary matting, and hydroculture, you can keep most plants happy for two weeks or even more. The plants that need the least care are those grown in sealed terrariums. They can often go for years without water!