Polygonum sp. "Kawagoeanum"
Author: Drinda Jacobson
Common Names: Polygonum sp. “Pink”
Order: Caryophyllales (Polygonales)
Native Distribution: Believed to be from Eastern Asia, growing at the water’s edge in wetlands such as swamps and ditches
Aquarium Placement: Background, midground in large aquaria
Requirements: Medium light, CO2 addition recommended
Polygonum sp. “Kawagoeanum” has a bamboo-like appearance. It is a rapid grower that is easily cultivated. Leaves can get up to approximately 3 inches in length, making the width of one stem up to 6 inches in diameter. Though this sounds large, the plant can easily be used in medium-sized aquariums due to its tiered, bamboo-like growth pattern.
Polygonum sp. “Kawagoeanum” branches easily and, unlike other Polygonum species, does not grow extremely vertical. It also has a tendency to grow stem roots, which can be an unsightly nuisance. These can be safely trimmed off with no damage to the plant.
With high light, phosphate, iron, and CO2 it can attain a beautiful red/magenta color on the ends of its leaves. This color gives way to an olive green as the light gets less intense. While this plant can take up nutrients from the substrate, water column nutrients are also readily used because it is a stem plant.
Polygonum sp. “Kawagoeanum” is often confused with Polygonum sp. “Sao Paulo.” It can be differentiated from the latter by its prolific branching habit, lack of true extreme vertical growth, and redder magenta color. Newer to the aquarium hobby, it is not usually found in stores or through online vendors. Hobbyists are the most reliable source of trade for this plant. The exact taxonomy of the plant circulating in the hobby is still uncertain, but its striking coloration should ensure its popularity.
Because of its striking coloration, Polygonum sp. “Kawagoeanum” can be a great focal plant. Its height and branching habit, as well as its not-so-desired loss of bottom leaves, make it a perfect candidate for a background plant. The hobbyist should know that this plant will require regular maintenance due to its quick growth.
Since Polygonum sp. “Kawagoeanum” naturally forms a dense branching bush, it is best suited for a naturalized aquascape rather than the neatly trimmed Dutch-style aquascapes.
It can be grown immersed or submerged. Clippings will root. It will flower immersed and produce seeds.