Lindernia grandiflora

The Blue moneywort, also known as Savanna pimpernel or False pimpernel, is not yet widely known as an aquarium plant. In its terrestrial form, however, it has long been grown as an attractive flowering ornamental plant with creeping or trailing shoots. This Lindernia species is native to Florida and Georgia in the subtropical south-eastern United States, where it grows in wetlands such as swamps and ditches, usually on sandy soils. On land, the shoots creep along the ground and form a dense carpet. They have small, rounded leaves and attractive blue-and-white flowers that are larger than those of Lindernia rotundifolia.
When grown submerged, Lindernia grandiflora looks quite different. The shoots grow upright, branch very little and do not produce flowers. The stems are about 1.5 mm thick. The opposite submerged leaves are ovate, up to about 1.5 × 0.9 cm in size, and medium to light green, often developing a slight reddish-brown tint under strong lighting. Individual shoots are about 3–4 cm wide, with internodes (the stem sections between the nodes) measuring around 1.5–2 cm. Under Aquarium conditions, this Lindernia grows at a moderate rate.

As an aquarium plant, Lindernia grandiflora has moderate care requirements. Medium to high lighting, temperatures of around 20–28 °C, soft to moderately hard water, and a complete nutrient supply through the water column are recommended. Additional CO₂ is not always essential but greatly improves growth. Propagation is by tip and shoot cuttings. It is best planted in groups by inserting individual shoots into the substrate a short distance apart. After trimming, the stems produce new shoots, although the plant generally branches very little when grown submerged. The shoots may exceed 30 cm in length, but for an attractive appearance it is best to keep the plants at a height of about 10–30 cm by regularly replanting healthy shoot tips.

This stem plant from southeastern North America is especially attractive when planted as a group in the midground of the aquarium, thanks to its open, upright growth. In small or nano aquaria, it can also be used as a background plant. Compared with the similar Lindernia rotundifolia, Lindernia grandiflora grows more slowly and therefore requires less maintenance. It is likely to tolerate temperatures well below 20 °C for short periods, as these can occur during winter in its native habitat.
As a creeping, freely flowering terrestrial plant, Lindernia rotundifolia is interesting not only for submerged use but also for emersed growth, for example in well-lit paludariums or Wabi-Kusa layouts. It combines particularly well with contrasting marsh plants from the subtropical southeastern United States.