Thunbergia alata: black-eyed Susan vine
The Thunbergia alata is an evergreen climbing plant used, in most cases, to decorated walls or trellises in bamboo wood; very beautiful is also the cascade effect in case, given the small size, it is planted in vases on balconies or on window sills.
Thunbergia alata is part of the Acanthaceae family and is native to Asia, South America and above all Southern Africa. It is a plant that grows very fast and has thin and woody stems in the lower part, which can reach a height of 3 meters. Its leathery leaves are oval, pointed and have a beautiful forest green color.
The main characteristic of the winged Thunbergia are however its trumpet-shaped flowers that bloom from June to September: they have an intense orange-yellow color which, towards the inside, darkens more and more until it reaches the black center: for this reason the winged Thunbergia it is otherwise known as black-eyed Susan vine. However, there are many varieties of Thunbergia alata and they differ substantially depending on the color of the flowers: these can in fact be red, white or pink.
Thunbergia alata can withstand temperatures of no less than 5 ° -6 °, but not for long periods, while it can not stand humid climates: this explains the fact that while in the warmer regions it manages to overcome the winter, regenerating in spring, in colder areas it is cultivated only as an annual plant.
It is a plant that prefers sunny places, even if in the torrid summer days, when the temperature tends to exceed 25 °, it is important to move the plant in a dim light.
The Thunbergia requires a soil that is just acidic, soft and well drained: it is recommended to insert cocci or pumice stone to avoid damaging water stagnations. It is necessary to keep the soil moist especially during the summer, but only when it is dry.
The month of September is the one for fertilizing, to be carried out every 20 days with a product rich in potassium and liquid, to be diluted in water; you can also use a granular fertilizer, but in this case it is good to use it every 2 months.
The winged Thunbergia can be attacked by mites or aphids, which particularly affect the flowers and shoots: just remove them with a cloth or with cotton wool soaked in water and Marseille soap.
We must then pay attention to the stagnant water that can cause root rot, yellowing of the leaves and their discoloration until complete fall.
The Thunbergia alata owes its name to the Swedish botanist Carl Peter Thunberg, a follower of the most famous Linnaeus.
Consider that in India and Malaysia this plant, placed on the temples, is used to treat headaches; in Kenya it is consumed as a salad or as fodder for the animals; in Tanganyca instead lymph drops are used to soothe ocular inflammations.