Water does more than help plants grow. It grows interest in your landscape as well. By adding a water feature, even just a container or two, you bring intriguing new plants into your gardening mix and create a soothing display.
Large vessels give plants room to grow, require less plant culling and keep water temps steadier, which limits algae growth and plant stress. The pot should be at least 6 inches deep and 15 inches wide and made of galvanized metal, steel, glazed terra-cotta or clay, ceramic or stone. (Zinc and copper can leach, and glass heats up too quickly.) A dark interior enhances the illusion of depth and hides algae.
Plant choice is as wide as container styles. Emergents, such as water lily, lotus and rush, sit in pots of aquatic planting soil below the water surface but can grow several feet tall and often have flowers. Floaters, such as water hyacinth and water lettuce, do what their name says: float. Their coarse leaves and flat shapes contrast with emergents and shade the water to help keep it cool. Floaters are apt to spread, so remove as necessary to maintain about 40 percent open water surface. If you have room, add submergents, which—again—do just what the name implies: live underwater and help keep the water clean.
Provide fresh, nonchlorinated, nonsoftened water and six hours of sun a day to ensure you get the most from your cool pool of plants.