Encyclopaedia
PlantFreshwaterAdvanced
©AI Generated·Proprietary
Heteranthera zosterifolia
Heteranthera zosterifolia
Spectacular 'Stargrass' from the Amazon basin. Thrives under intense light and CO2, growing thick, horizontal star-shaped bright green tips.
Class:Liliopsida
Order:Commelinales
Family:Pontederiaceae
Genus:Heteranthera
Species:Heteranthera zosterifolia
Share
Check out Heteranthera zosterifolia on Atlarium
Water Temperature
20 - 28 °C
pH Value
6 - 7.5
Water type
Freshwater
Light
Medium
CO2
Medium
Expected height
40 cm
Expected width
15 cm
GH
3 - 8 dGH
KH
0 - 21 dKH
Species description
Geographical Origin and Habitat: Heteranthera zosterifolia, simply known as "Heteranthera" or Stargrass, is a spectacular amphibious stem plant endemic to Brazil, Argentina, and vast areas of the Amazon rainforest (South America). It evolves along the banks, in flooded ditches, in muddy swamps, and in slow-flowing or stagnant rivers (igarapés). Seasonal variations (rainy season and dry season) force this plant to frequently switch from the submerged to the emersed form and vice versa.
Taxonomy & Genetics: It is a monocotyledon belonging to the Pontederiaceae family (a biological relative of the infamous Water Hyacinth, *Eichhornia crassipes*). The name derives from the Greek *heteros* (different) and *anthera* (anther, the male parts of the flower). If left to emerge from the water surface in open aquariums, it shows its magnificent genetics by blooming copiously: it produces wonderful and extremely delicate six-petaled bright blue-violet flowers, which open for only one day.
Physical Structure: The submerged architecture is caulescent and bushy. It possesses pale, fleshy, and soft stems. The leaves are not arranged in whorls, but are alternate, flat, strictly linear, or lanceolate. They grow in a compact rosette at the apex of the stem, creating a sort of small geometric star, hence the common Anglo-Saxon name "Star Grass". It emits white adventitious roots in profusion on the lower and intermediate nodes.
Color & Texture: It provides one of the brightest and most luminous greens available in the planted aquarium hobby: a vital and almost golden light green under the lights, capable of breaking the monotony of the dark reds or somber greens of neighboring plants. It never takes on reddish hues. The submerged leaf is smooth and very soft, making the bush extremely buoyant and dancing under the filter current.
Care, breeding and tankmates
Lighting & CO2: Extremely demanding if you want to achieve the perfect "star" bush. The plant does not tolerate shadows: if the light is weak (PAR < 50), it blackens at the base, elongates the internodes out of proportion, and loses the underlying leaves (etiolation). With very strong light (PAR > 80), it grows thick, horizontal, and shrinks the apical stars. CO2 is practically mandatory to make it shine and guarantee lush growth rates; otherwise, the plant degrades or dies of carbon starvation.
Nutrition & Substrate: An authentic indicator (biosensor) for nitrates and phosphates. It roots powerfully in fertile substrates (allophanes or enriched sands) but feeds greedily on dissolved compounds in the water. A water column lacking macronutrients (NO3 < 5 ppm) causes Heteranthera to turn yellow, stop growing, and turn black within three days. A substantial weekly water column fertilization plan is essential for its well-being.
Water Chemistry: Like most Amazonian endemics, it loves the soft, warm, and acidic waters classic of the South American biotope (pH 6.0-6.8, GH 3-8, Temperature 22-27°C). Very hard waters or those with a strongly alkaline pH hinder the absorption of iron and cause chlorosis, with apices turning white or transparent instead of bright green.
Space Management & Placement: The undisputed star for creating the iconic horizontal "streets" (Dutch street) in Dutch Style aquascaping. It should be positioned in the midground or background. Planting it in asymmetrical bunches or ascending terraces, placing the shortest cuttings in front and the longest behind, will create a formidable compact green block with an almost lawn-like but elevated appearance.
Pruning: If the conditions are suitable, the growth rate approaches the monstrous. Ruthless weekly topping must be carried out, drastically lowering the height of the bush. The axillary buds will explode, producing very thick branches in two days. Have no mercy, or the plant will touch the surface, expanding horizontally and suffocating everything below with darkness (only to rot at the base itself).
Risks & Diseases: In addition to the lethal risk of Nitrate and CO2 deficiency, which literally dissolves its stems into green mush, the true chemical "Achilles' heel" of Zosterifolia is Iron. An Fe deficiency is noticed instantly: the new apical shoots blacken and die (meristem necrosis), irreparably blocking the growth of the top, forcing you to cut below the necrosis.
Geographic Origin and Distribution
Heteranthera zosterifolia, simply known as "Heteranthera" or Stargrass, is a spectacular amphibious stem plant endemic to Brazil, Argentina, and vast areas of the Amazon rainforest (South America). It evolves along the banks, in flooded ditches, in muddy swamps, and in slow-flowing or stagnant rivers (igarapés). Seasonal variations (rainy season and dry season) force this plant to frequently switch from the submerged to the emersed form and vice versa.
Origin
Amazon, Orinoco, and GuianasExtra-Amazon South America
Plant profile
- Placement
- No verified data available
- Botanical form
- No verified data available
- Growth
- No verified data available
- Substrate
- No verified data available
- Column fertilization
- No verified data available
- Root fertilization
- No verified data available
- Trimming
- No verified data available
- Propagation
- No verified data available
- Nutrients
- No verified data available
- Sensitivity
- No verified data available
- Layout role
- No verified data available
Image gallery
Licensed images linked to the species or, when marked, to the closest representative taxon.
Related species
Recommendations grouped by close relatives, companion choices, and similar care.
