February 07, 2025 2 min read
Eriocaulon ratnagiricum is an endangered species native to India. It has been available in the hobbyist aquarium trade for some time, although it has not been commercially bred on a large scale. Its distinctive spiny appearance distinguishes it from other plant species. Eriocaulon ratnagiricum is one of the smallest Eriocaulons, with an adult size of about 2.5 inches. It also flowers less frequently under water than other Eriocaulons such as E. polaris or E. cinereum. This allows it to grow in its attractive porcupine shape for a long time.
It has a reputation for being difficult to grow, but once its requirements are understood it is actually quite easy to grow and propagate. It is a fast growing plant with good hardiness provided its growth requirements are met.
This plant grows very well in ammonia rich aquasoils and the use of rich, acidic substrates will speed up growth considerably. It grows better with higher light and CO2 levels than more basic aquarium plants. As a short plant - it's important to direct the flow/CO2 to the substrate zone and ensure it is not shaded by taller plants. It is KH sensitive and should be kept in low alkalinity water (less than 3dKH). This means it is not suitable for tanks with Seiryu rock.
It has a large root system despite a rather short crown. The substrate should not be too thin (less than 2 inches) if you want it to grow to a good size.
Flower stems should be removed if they appear, otherwise the plant may put most of its energy into flower stem growth rather than vegetative growth.
Small plantlets next to some young Eriocaulon ratnagiricum. These are planted far too close together for each to grow to full adult size; this is fine if the intention is to uproot them before they are fully grown (for sale or further propagation).
The plant will sometimes naturally produce baby plants as it grows. However, in stable tanks the plant will often not divide frequently and will simply grow larger over time. Sometimes uprooting, replanting or damaging the plant can cause plantlets to form, but the better method is to manually split the Eriocaulon into even halves - both parts will grow into separate plants.
Eriocaulon ratnagiricum has a tendency to produce many baby plantlets from each half when divided into two halves. This results in a cluster of smaller plantlets around each crown. If left to their own devices, the plantlets may suffer from overcrowding - the cluster should be uprooted and the plantlets separated and planted individually. Each plantlet will tend to grow into a full-sized plant in time.
You can read more on propagating Eriocaulons on this page