Source: Wikimedia Commons
Downoi
IntermediatePogostemon helferi
A beautiful foreground-midground plant with star-shaped wavy leaves. A unique aquatic plant from Thailand.
About
Pogostemon helferi is an aquatic plant in the family Lamiaceae native to the borderlands of Thailand and Myanmar, where it colonizes shallow, fast-moving streams. It is known locally as 'Downoi' (meaning 'little star' in Thai), a name that perfectly captures the distinctive star-shaped, crinkled leaves that set it apart from virtually every other aquarium plant. Used in foreground to midground positions, its unique leaf architecture provides textural contrast within compositions. Brighter illumination and CO2 injection improve both coloration — healthy specimens achieve a rich, deep green — and growth rate, which is otherwise moderate. It is somewhat sensitive to abrupt changes in water chemistry and benefits significantly from nutrient-rich aquasoil. Discovered and popularized by Thai aquarists, it spread to the global hobby and has since become a sought-after species prized for its botanical uniqueness.
Basic Info
Origin
Border region of Thailand and Myanmar
Lifespan
Perennial
Size
3-10cm
Temperature
20〜28℃
Watering & Fertilizer
Root tabs, CO2
Growing Tips
Coloration
CO2添加で成長と発色が改善
Lighting
明るめの照明が必要
Feeding
底床は栄養系ソイルが適する
Breeding
子株で増える
Notes
水質は弱酸性〜中性が良い
Downoi FAQ
QWhat is the growing difficulty level for Downoi?
Intermediate. A variety suitable for intermediate growers. Requires some cultivation experience and knowledge of environment management. Pay careful attention to temperature and humidity control.
QWhat is the ideal temperature for Downoi?
The ideal temperature for Downoi is 20〜28℃. Avoid sudden temperature changes and maintain a stable environment.
QWhat is the lifespan of Downoi?
The average lifespan of Downoi is Perennial. With proper cultivation environment and nutrient management, you can keep it healthy for a long time.
QHow large does Downoi get?
The mature size of Downoi is 3-10cm. This may vary slightly depending on cultivation environment and individual differences.
QHow should I water and fertilize Downoi?
Downoi: watering & fertilizer — Root tabs, CO2. Aim for appropriate frequency and amount.
QWhat is the typical price for Downoi?
The price of Downoi varies significantly by variety, characteristics, size, and lineage. Please check ボタちょく's price guide for the latest market information.
Last updated: June 24, 2026
References & Sources
Edited & verified by: BoTachoku Editorial Team
The classifications, regulations, and growing data on this page are created and verified based on the primary information database below.
Taxonomy & Authority
Regulations & Conservation Status
Sources: 環境省 特定外来生物等一覧(外来生物法) / CITES Appendix II 植物掲載分類群(科・属レベル)
Regulations may change. Always verify the latest information with the relevant authorities.
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