By the Pond Lady
You cannot have a Water Garden without plants. A modest water garden can be contained in a barrel or trough or you can have an elaborate pond with streams, fountains and waterfalls. Which ever one you choose, a combination of plants will not only make it beautiful, but healthy. Aquatic plants play essential roles in the pond.
Submerged plants are those that grow fully immersed in the water. They get their nutrients directly from the water through their leaves rather than through their roots in the soil. Underwater plants play a vital role in water gardening. They compete for the nutrients in the water that promote algae growth. They provide the fish with some food. They help oxygenate the water. They also provide hiding places for your fish if they feel threatened. One bunch of submersed aquatic plant per square foot of water surface in a pond that is not overstocked with fish will keep the pond water clear. Some of the best-submerged plants to have in your pond to help keep the water clear is:
Cabomba caroliniana. Subtropical (will not over winter outside) with bright green, fan shaped, flat-leaved up to1.5 inches in diameter. Surface leaves are linear with pointed tips. It produces a charming white flower at the water’s surface. The flower is several times as large as the very tiny white bloom of Anacharis and the equally tiny purple bloom of Elodea.
Elodea canadensis. North American native (a smaller leave version of the commonly sold Anacharis) that breaks dormancy earlier than other submersed plants. Elodea is an ideal plant for preventing spring algae blooms. Plant this in soil or pea gravel. Elodea is hardier than Anacharis.
Ceratophyl lumdemersum. Coontail, Hornwort. North American native That wintersRead more on backyardgardener.com