How to grow Sygonananthus species

Above: Syngonanthus 'Lago grande' has light green foliage that contrasts well with red/orange colored plants. 

Syngonanthus macrocaulon

Syngonanthus macrocaulon is found in the Amazon in very soft black water rivers. It was first introduced to the hobby as "Tonina sp. belem", but was later confirmed by botanists as belonging to the genus Syngonanthus. Some dealers mistakenly call it Syngonanthus belem, combining old and new names.

Similar plants in this category are Syngonanthus 'Manaus', which looks similar to Macrocaulon but is considerably taller/bigger, and 'Lago grande', which is similar in size but has a spiked top compared to Syngonanthus macrocaulon. All have similar growth requirements.

Syngonanthus macrocaulon is a stem plant that will produce side shoots as the plant grows taller. It is best used as a mid-ground shrub and its pale green colour contrasts well with red/orange plants.

This plant has a long history in the hobby, but in the early years when its requirements were not well understood, it had a reputation for being difficult to keep. With the development of aquasoil substrates - which are acidic and buffer the KH/pH in tanks - this plant can now be considered fairly easy to grow as long as the tank has very soft water and aquasoil. Soft water is critical for this species. Soft water + regular water column dosing will also work.

It needs good light levels to grow well, so Syngonanthus species should not be shaded. CO2 injection should be present but does not need to be high. A nutrient rich, acidic soil substrate is a significant advantage in growing Syngonanthus species.

Syngonanthus macrocaulon has a distinctive mop / umbrella shaped top. Planting them at staggered heights will produce beautiful clusters.

Syngonanthus giant is significantly larger than Syngonanthus macrocaulon/lago grande. Syngonanthus manaus and Syngonanthus giant are the 2 larger Syngonanthus species.

Key success factors

• Soft water ( <2 dKH ).
• Sufficient light (medium level onwards).
• Rich, acidic aquasoil substrates makes it easy.

Trimming and propagation

This species does much better with topping and replanting - cutting off the top 4 to 6 inches, discarding the older lower part of the plant and replanting the top.

The plant will naturally produce several side shoots as it grows taller. These can be cut off and replanted as individual plants.

Syngonanthus 'Lago grande' has a spikier top than Syngonanthus macrocaulon. It is good for forming dense bushes over time.