Out of all of the different types of water plants, it’s the oxygenators that are the most diverse in their uses and they play the biggest role in maintaining healthy, clean water. They remove excess nitrates by filtration preventing green water while at the same time, releasing thousands of small bubbles of oxygen back into the water. These diverse, submerged plants also provide valuable cover for all types of pond life and make an excellent spawning and egg laying environment for Fish, Frogs, Toads and Newts.
Certain species of submerged plants are sold as oxygenating plants but could also be categorized as deep marginal plants. Sagittaria Graminea and Hippuris Vulgaris would certainly fit into both categories. Different types of pond weed prefer different locations such as in lakes, ponds, canals dykes and ponds. They grow in variant conditions such as sun or full shade or shallow and deep water. Many self- seed and can be rather invasive in clay bottomed ponds but all varieties can be easily maintained in lined and fibreglass ponds. Oxygenators are sold bare rooted or in stem cut bunches. In natural ponds they can be planted straight into clay, but in pre-lined ponds, they need planting into Hessian lined, Aquatic Baskets or planting bags. Using aquatic soil and a top dressing of aquatic gravel, all varieties root freely and planting is achieved by simply burying one third of the plant under the soil.
Suitable for shallow water and streams
The following species do best in shallow water up to 36 inches deep and will adapt to free flowing or still water in full sun or shade. Callitriche species, Myriophyllum species, Vallisneria species, the attractive white flowering Ranunculus (Water Crowfoot) species and Hippuris Vulgaris.
Suitable for deep water, Aquatic baskets and clay bottomed ponds
The following species are good for colonising natural areas but will also grow quite happily in all garden ponds in full sun or shade. Cerotophyllum species also known as (hornworts), Elodea species (most popular and commercially sold oxygenating plants), and Potomogeton species also known as (True Pond Weeds).
Oxygenators with floating leaves
The following species not only produce oxygen, but also produce hundreds of leaves that float on the water surface providing attractive looking cover for pond creatures, Hydrocotyl species and cultivars, Callitriche species and Ranunculus species (Water Crowfoots) and Potomogeton species.
Some oxygenating plants do best in clay or silt bottomed ponds where they creep along the bottom forming dense underwater mats. Eleocharis Acicularis, Callitriche species and Ludwigia Palustris, these varieties grow up into the shallows and out onto the banks making an excellent exit and entrance for visiting wildlife and a great exit for young Newts, Frogs and Toads.
Oxygenators with leaves that grow up out of the water
Hippuris Vulgaris, Myriophyllum species and Sagittaria Graminea, these species produce under water leaves that grow up out of the water taking on an entirely different form and growing habit.
Beware of planting out in your pond if you have Carp. Koi-Carp and Grass Carp especially will definitely love you for providing this picnic for them and will happily munch through every last stem.
Picnic Baskets are provided at your peril !!!