A genus that includes numerous evergreen shrubs from Africa and South America. The Tibucina plants have a slightly climbing or drooping habit, and develop to a height of about one metre. The stems are green, semi-woody, arched; the leaves are large, oval, rough, dark green, crossed by deep veins, leathery. Throughout the summer, the tibucina produces showy inflorescences consisting of clusters of spectacular flowers of intense purple color.
The species usually most cultivated as an indoor plant is T. semidecandra, Tibouchina urvilleana, the variety with the largest cultivation, of Brazilian origin, is also cultivated as a garden plant in regions with mild winters.
These plants love very bright positions, but far from direct sunlight, which could damage the leaves and flowers, in the warmer months of the year should be shaded. These plants love the heat, therefore they can spend the warm months outside, in the garden or on a terrace, but they are to be immediately withdrawn from the house in winter, as they fear temperatures below 10-12°C.
In the house, they are to be placed in a very bright place, far from the direct rays of the sun and from the air currents.
During the vegetative period, from March to October, water regularly the tibucine plants, also every day, avoiding to let the soil dry up; during the cold months, water the Tibouchina urvilleana occasionally, at least once a week, keeping the soil always slightly moist, but not soaked in water. It is also advisable to provide vaporization on the leaves, to allow the plant to maintain the correct degree of humidity.
During flowering, provide fertilizer for flowering plants every 10-15 days dissolved in the water of the watering.
The tiboucine prefers loose, sandy, very well drained soils, tending to be acidic; use good balanced soil, mixed with peat and a small part of lapillus or pumice for increasing the drainage.
The Tibouchina urvilleana plant has a growth and development depending on the size of the pot; in fact, the bigger it is, the more the plant will grow quickly.
It is good to plan to repot the plant every year at the beginning of spring, using gradually larger pots up to 30 cm in diameter.
The multiplication of the plants of Tibouchina urvilleana takes place by cutting, and is done in spring, rooting the new shoots in a mixture of peat and sand in equal parts and in a place with mild temperatures, around the 21-24 °C; once rooted, the cuttings are to be repotted in single containers and treated as adult plants.
Tibucina – Tibouchina urvilleana: Parasites and diseases
Wrong cultivation techniques can favour the onset of radical rottenness; sometimes the new shoots are attacked by aphids which completely ruin them. The red spider can be a problem for plants of this kind and, to counteract it effectively, it is good to increase the environmental humidity and intensify the vaporization of water on the leaves, since water is an element not liked by the spiders. If the problem is widespread, it is advisable to intervene with specific insecticide products.