Pogostemon quadrifolius

The Four-leaved star plant is still relatively new to the aquarium hobby and soon turned out to be an undemanding, very fast-growing and also beautiful stem plant. It was first introduced to Europe from Laos as Pogostemon stellatus "Octopus", and in 2013 its true identity was revealed. Pogostemon quadrifolius is widespread from India and Bangladesh to Southeast Asia as a marsh and water plant. It has whorls of mostly four leaves at the stem nodes, to which the species name P. quadrifolius refers. In the submerged form (submersed) its leaves are about 12 - 14 cm long and 3 mm wide. They are often curved sideways, hence the trade name "Octopus". The underside of the light to medium green leaves is partly tinted pale purple and the shoot tips can turn reddish-brown. The stems, about 3.5 mm thick, grow loosely upright or to the side and are moderately branched.
In the terrestrial form (emersed) the leaves are broader and shorter than in the submerged plant. Planted in the aquarium, the emersed stems soon form submerged shoots with the typical long, narrow leaves.

Leaf structure of the submerged leaves

Of all the Pogostemon species known so far as aquarium plants, P. quadrifolius is the easiest to keep. The Four-leaved star plant also grows in aquariums with moderate lighting and without additional CO₂. However, a good supply of macro- and micronutrients greatly promotes the already fast growth. This Pogostemon grows at low to high carbonate hardness and at temperatures between about 20 - 28 °C. Occasional pruning promotes bushy, branched growth. Propagation is by head cuttings and partial cuttings.

The four-leaved water star is a large stem plant that appears graceful with its very narrow, curved foliage. Especially in low light, the plant has a loose, spreading growth pattern, the shoots often virtually "snake" through the aquarium. Pogostemon quadrifolius looks best in large aquariums as a stand at least 30 - 40 cm high in the middle to background. As a very fast-growing, easy plant that is less demanding than e.g. Pogostemon stellatus, it is recommended for aquarium beginners and for the initial planting of newly established tanks. Pogostemon quadrifolius is also interesting for Asia-themed biotope aquariums.