Pogostemon Helferi | Aquatic Plant

Pogostemon helferi, commonly known as “Daonoi” or “Downoi,” is a unique plant found in fast-flowing rivers of northwest Thailand on limestone. Although known to science for over a century, it gained popularity in the aquarium hobby in 1996. Characterized by compact growth, curly leaves, and a light green hue, it’s become a favorite for aquarium fore- and middlegrounds.

In its natural habitat, P. helferi grows on limestone rocks submerged in fast currents during the rainy season and forms upright shoots with flower spikes in autumn and winter. Cultivation requires adequate lighting, CO2 supply, and nutrient levels, especially iron, to maintain its lush green color. Insufficient light can cause elongation of internodes and a yellowish hue.

Propagation is straightforward through cuttings, planted shortly below a node with trimmed lower leaves for better anchorage. It’s suitable for nano or small aquariums in the middleground and larger tanks in the foreground. Care should be taken during handling to avoid bruising, which can lead to dieback. It can also be attached to wood or rocks using nylon thread, making it suitable for paludariums where it can be cultivated partially emersed and partially submerged.

Aquatic Plant Information – Pogostemon helferi:

• Common Names: Downoi
• Synonyms: Anuragia helferi (Hook. f.) Raizada, Dysophylla helferi Hook. f., Eusteralis helferi (Hook. f.) Panigrahi
• Botanical Name: Pogostemon helferi (Hook. f.) Press
• Family: Lamiaceae
• Genus: Pogostemon
• Difficulty Level: Medium
• Usage: Suitable as an Epiphyte (growing on hardscape), ideal for Midground and Nano tanks, also suitable for Foreground, can be grown in groups
• Growth Rate: Medium
• pH Range: 5 – 7
• Temperature Tolerance: 15 – 28°C
• Carbonate Hardness (KH): 2 – 14°dKH
• General Hardness (GH): 0 – 30°dGH
• Propagation: Can be propagated through Cuttings, Splitting, or cutting off daughter plants
• Emersed Growth: Yes