Vallisneria americana sp ‘gigantea’ is a genus of freshwater with long leaved grass-like aquatic plant. This plant will get rather large and will form a dense cover at the water surface which will aid in the control of free floating algae (green water).
In most aquariums the leaves grow so long that they float on the surface. Vallisneria americana sp. ‘gigantea’ leaves arise in clusters from their roots. Leaves grow up to 120cm (47 inch) long and 12mm (0.4 inch) wide. So the plant needs pruning to stop it taking too much light from plants growing beneath. The leaves are tough and strong, so they are not normally eaten by herbivorous fish, dark green coloured with rounded tips and definite raised veins. They generally grow in cycles, thriving for 3 or 4 months and then dying off for another few months.
It is dioecious and individual plants are either male or female. Individual pistillate flowers have three sepals and three white petals, and occur in a tubular spathe that grows to the water surface at the end of a long peduncle.
Staminate (male) flowers are crowded into an ovoid spathe borne on a short peduncle near the base of the plant. Eventually the spathe of staminate flowers breaks free and floats to the surface where it releases its flowers. Fertilization occurs when male flowers float into contact with female flowers. When fertilization is complete the peduncle of the pistillate flower coils up and fruit develops underwater. Fertilization produces a long cylindrical pod containing small, dark seeds.
The plant has a large range of water temperature from 20 to 28°C (68-82°F) and takes full sun to light shade; growth will be faster and stronger under brighter light. It does well in a mixture of fine sand with a medium light level. Iron is important for this plant, and the best way to ensure that it gets the right quantities is to use an iron-rich substrate. Recommended substrate for growing is gravel.
When planting it, always leave the crown of the plant above the substrate, this is easy to spot as the crown will have a lighter colouration as the rest of the plant.
This plant is grown locally (Malta) by one of our partner aquarium plant keepers/breeders and is sold as a single rooted plant in this product listing.