Ludwigia sedoides

This Ludwigia with its floating rosulate leaves is home to Central and South America, where it grows in stagnant waters or river zones with a very weak current. It bears a striking resemblance to water caltrop (Trapa natans), to which it is unrelated, though. Ludwigia sedoides is a very common pond plant in warm climates or ponds in conservatories. Cultivation in an aquarium is a bit more complicated. This species is known as "mosaic plant" in some English-speaking regions.

First and foremost, Ludwigia sedoides needs lots of light (0.75 watts per litre and over, or direct sunlight). Its extreme light hunger makes it a difficult plant to cultivate in an aquarium. Outdoor cultivation (during the warm season) is sometimes the only solution to achieve satisfying growth in this species. It also needs a good supply of macro- and micronutrients. Optimal conditions cause it to form yellow flowers.

L. sedoides is propagated by cutting off the floating rosette. A piece of the stem ought to remain on the rosette. The main part of the stem is left in the tank. A new rosette will develop on it after a short while.

Even though only of limited use in aquarium layouts, this plant with its unique reddish floating rosettes is very well-suited for (warm) ponds and possibly also in strongly lit paludaria.