General Information
The genus Angraecum comprises about two hundred species of orchids, native to Southern Africa, predominantly found in Madagascar; they are pseudobulb-less, epiphytic, and vary in size, with some species being almost miniature, while others have vigorous plants and very large flowers. The flowers are pure white, sometimes greenish or tinged with yellow or pink.
Angraecum sesquipedale has very large, star-shaped white flowers; a long spur, which can reach 25-30 cm in length, develops at the base of the corolla. This orchid was discovered by C. Darwin around the mid-1800s. It has long fleshy leaves that grow in pairs along the vigorous stem, and Angraecum sesquipedale plants can reach 30-40 cm in height. The flowers are very fragrant, especially during the evening hours. The plants tend to develop long, silver-green aerial roots.
Exposure
Angraecum prefer very bright locations, but away from direct sunlight, at least during the hottest hours of the day and in summer; they can also be kept on window sills, taking care to shield the sunlight with a light curtain. They are sensitive to cold and prefer night temperatures above 15°C. In summer, it is advisable to leave them in a shaded, well-ventilated, and fairly cool place, trying to avoid prolonged exposure to temperatures much higher than 35°C.
Watering
Angraecum do not have a true resting period, so they should be watered regularly throughout the year, keeping the substrate slightly moist. However, ensure that the substrate is not too waterlogged, as dangerous root rot could quickly occur.
After flowering, watering should be slightly reduced for about a couple of months. During the period of vegetative growth and flower production, a specific orchid fertilizer, at half dose, should be given every 20-25 days.
Substrate
Like many other epiphytic orchids, Angraecum are grown in small containers, filled with shredded bark, small pieces of polystyrene, perlite, and other incoherent materials, suitable for simulating the soil in which they grow in the forests of Madagascar.
These plants should be repotted when the roots are constrained within the pot, taking care to use a pot only slightly larger than the previous one. To avoid problems with this operation, it is advisable to moisten the roots, so that they are less fragile.
