Ludwigia Inclinata Var “Cuba” (formerly Ludwigia sp. ‘Cuba’) is a beautiful, showy, large stem plant which grows both submersed and emersed in swamps on the Isle of Youth, a small island off the southwestern coast of Cuba. Although having ovate, green leaves typical of the Ludwigia genus when emersed, this stem plant develops long, narrow leaves marbled with red and orange highlights when submersed. Despite its unique appearance, it is but one of many geographical variations belonging to the species Ludwigia inclinata, all of which are united into one species due to the fact that they all bear the same large, yellow flower. L. inclinata var. verticillata ‘Cuba’ was recently introduced to the hobby thanks to the efforts of the Tropica aquatic plant nursery. Although still uncommon in the trade, it should become significantly more popular and common in the future.
This Ludwigia makes several demands on the hobbyist before showing its full potential such as intense lighting, CO2, a well balanced nutrient regime, and space. However, when conditions are good, this stem plant grows rapidly. Intense lighting is necessary (aim for at least 3 watts per gallon). CO2 supplementation is a necessity; without it, this plant develops broader, greener leaves, produces fewer leaves per whorl, and grows more slowly. Nitrate (5-15 ppm) and phosphate (1-2 ppm) supplementation through the water column is necessary for good coloration and health. Heavy iron and micronutrient fertilization with a reliable liquid fertilizer is also necessary for this species; if new growth is white, this plant is not receiving enough iron.
Ludwigia Inclinata Var “Cuba”, like others of the Ludwigia genus, grows at an angle above the substrate under good lighting. Profuse branching coupled with rapid growth when under good conditions makes this plant highly invasive in the planted aquarium. Nonetheless, this plant does not handle repeated, intense prunings very well. If pruned across the top, the rooted portions of Ludwigia Inclinata Var “Cuba” often turn black and melt away. Instead, this plant should be topped and replanted each time it is pruned.