Hemianthus callitrichoides

Hemianthus callitrichoides — commonly abbreviated 'HC' and known in the trade as 'Cuba' — is a semi-aquatic plant in the family Linderniaceae endemic to the West Indies, with native populations on the Bahamas, Cuba, Hispaniola, Jamaica, and Puerto Rico. Among the smallest flowering plants on Earth, individual leaves measure approximately 1 mm in diameter. In aquascaping it is revered as the ultimate foreground carpeting species: its micro-leaves interlace to form a seamless green lawn of extraordinary density, a centerpiece of international-level competition layouts. High light and pressurized CO2 injection are absolute requirements — without both, the carpet progressively deteriorates. Establishing the initial carpet is the most challenging phase, demanding careful attention to temperature stability and balanced fertilization. Its combination of supreme beauty and technical difficulty makes it the pinnacle of foreground plant cultivation.

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