Lindernia dubia
Lindernia dubia is a plant that is widespread in the waters of East America. It can be found growing along the banks of rivers and lakes in sandy substrates. At one time, doubtful lindernia was introduced to Europe, where it became acclimatized to the conditions of local waters. This plant, compared to Lindernia rotundifolia and Lindernia parviflora, is rarely found in hobby aquariums.
Lindernia dubia has erect, branched stems, up to 20-40 cm long, with the leaves facing each other. The leaf blade is glossy, ovate or elliptical in shape, broad at the base, finely serrated, about 2.5 cm long and about 1.2 cm wide. The growth rate is medium. The plant's vertical shoots make it suitable for keeping in a Dutch-style aquarium, where it can be used to form attractive compositions. The greatest effect can be achieved by planting the bushes in groups.
The plant growing under water has an upright stem with oval leaves arranged in pairs. Upon reaching the surface of the water, the leaves take on a delta-shaped shape. Under suitable conditions, the doubtful lindernia may flower, producing single, pale purple flowers. Plant the shrubs in the aquarium in the middle and background.
Water parameters: temperature 20-26° C, hardness dH 4-15°, acidity pH 5,0-7,0. Nourishing substrate and feeding with CO2 and mineral fertiliser is necessary.
Use coarse river sand or a mixture of coarse sand and fine gravel as substrate.
Bright light with an intensity of 0.6 W/l is recommended. Daily light duration 10-12 hours. It is advisable to allow direct sunlight into the aquarium from time to time.
Reproduction
Lindernia dubia is propagated by dividing the stem. This requires an adult shrub should be carefully cut off the tip with a few leaves and planted in the ground by fixing it in a small stone.
The plant feels great in a moist pallidarium where it grows and flowers relatively quickly (June to September). After flowering, a fruit is formed in which, over time, yellowish seeds mature. You can try growing new bushes from seeds sown in moist sand, but this is not always successful.