Solanum uleanum

Solanum uleanum is a tropical climber from the nightshade family that stands out with its spectacular color change of the foliage – new leaves emerge in an intense, almost neon purple, then mature to a deep green with a purple underside. The fine hair on the leaf surface gives them a velvety texture, making this plant a strong “collector’s piece” in a humid tropical terrarium.

Purple that turns into green

In good conditions Solanum uleanum constantly produces fresh purple leaves – the stronger (but still diffused) the light and the higher the humidity, the more intense the coloration. Over time the leaves darken, turn green and contrast nicely with the purple underside and fine hairs on both leaves and stems. Against a background of uniformly green tropical plants this nightshade looks almost “backlit” – especially under high quality lighting.

Origin and natural habitat

Solanum uleanum comes from the humid rainforests of Brazil, Peru, Colombia and Ecuador, where it grows as an understorey plant – climbing tree trunks, mossy backgrounds and branches or creeping across the forest floor in partial shade. In a terrarium it works very well as a climber trained over a background, roots or branches, and with good support it can even start to “shingle” along the wall, forming a dense leafy cover.

Terrarium cultivation – not for the lazy, but very rewarding

As a plant from a humid rainforest, Solanum uleanum requires high humidity (70-90%) and a constantly slightly moist but well drained substrate. It performs best in loose mixes based on peat or coco fibre with bark and perlite added. It does not tolerate drought – if the substrate is allowed to dry out completely, it will quickly drop its leaves. At the same time it dislikes “standing water” around the roots, so good drainage and removal of excess moisture are essential.
The plant prefers bright, diffused light – a position that is too dark will cause the purple color to fade and the shoots to stretch, whereas too strong, direct light can scorch the delicate foliage. After planting or pruning it can be a bit temperamental: it needs stable conditions, good air circulation and patience. Once established, it grows quickly, thickens readily and produces many new shoots that can be used as cuttings.

Which setups is it suitable for?

Thanks to its climbing habit, Solanum uleanum works very well in:

• tall tropical terrariums with a structural background,
• vivaria with frogs (for example poison dart frogs), where it creates natural “green walls”,
• paludariums, as a terrestrial plant above the waterline,
• show tanks where one strong, visually striking plant accent is needed.

Leaves and stems, as with many members of the nightshade family, are considered potentially toxic – this species is better suited to enclosures with insectivorous reptiles and amphibians, rather than herbivorous or omnivorous animals that might nibble on the plants.
IMPORTANT: do not allow the substrate to dry out completely or humidity to fluctuate dramatically. In air that is too dry and under weak light, Solanum uleanum quickly loses its purple coloration and drops its leaves.

Solanum uleanum – growing conditions:

• Substrate: loose, organic, well draining mix (peat, bark, perlite)
• Air humidity: high, ideally 70-90%
• Temperature: optimally 20-28°C, avoid drops below about 15°C
• Light: bright, diffused; no direct sun
• Watering: substrate constantly slightly moist, without waterlogging
• Training: along the background, roots, branches or as a hanging plant