Hygrophila polysperma (Emergent)

Hygrophila polysperma is one of the most widely kept aquarium plants, valued for its hardiness and rapid growth. In its emergent form it produces noticeably larger, broader, light-green leaves and compact whorls of small lilac-pink flowers along the upper nodes — a floral display rarely seen when it is grown submerged. The emergent form is sturdier and more shrubby than the submersed form, with a self-supporting upright habit.

As one of the most forgiving of all aquatic stem plants, H. polysperma emergent is an ideal choice for beginners establishing the riparian zone of a new paludarium. It tolerates a wide range of temperatures, light levels, and water chemistries. Its rapid growth rate makes it an effective nutrient sink in heavily stocked builds, and regular trimmings provide abundant propagation material.

Light: Medium; 1,500–4,000 lux; flowers freely produced under medium-high light. CO2/Humidity: No CO2; keep roots submerged or in saturated substrate; emergent stems in humid air. Fertilisation: Weekly dilute all-purpose fertiliser into the aquatic section; fast grower with high nutrient demand. Placement: Plant in substrate at or just below the waterline; allow stems to grow upward into the paludarium air zone. Propagation: Stem cuttings replanted in substrate; one of the fastest-rooting aquatic plants available.