Irrigation for the Landscape - In order for a plant to grow, it needs nutrients, light, chlorophyll, heat and...water. There are many ways to deliver the needed amount of water to our ornamental landscape plants. These range from hand watering each plant to automated systems that provide water based on a timer. Soon, even more sophisticated systems will be available that are based on sensors placed near each plant. No matter the method, each plant in your garden has a certain requirement for water that must be met in order to have a happy plant.