Orchids of Africa and Madagascar
The orchids of Africa and Madagascar offer the grower some of the most exotic and beautiful of all orchids. They easily illustrate a great diversity of types, ranging from the very petite Mystacidiums, to the most impressive Ansellias, found high in the trees above giraffe level, seeking the light. Often credited for creating tremendous excitement at first discovery centuries ago, this group of orchids continue to reward modern growers even today.
Angraecoids, in particular, have enjoyed a special attraction since their discovery. By now, everyone has heard the story about Charles Darwin postulating that the pollination of Angraecum sesquipedale had to be due to an exceptionally long-tongued moth. Some years later the moth was discovered performing his duty, and named thusly named Xanthopan morganae predicta, in honor of Darwin's prediction. This group of orchids is well known for predominately pristine white flowers (with a few beautiful exceptions) that are, for the most part, very fragrant at night. The scent is just fantastic and with some species will fill an entire room with a sweet fragrance. Angraecoids vary dramatically in their size, making them a great choice for all growers. Some are also quite cold tolerant making them both more durable and in some cases perfect plants for outdoor growers here in Southern California.
The orchids of Africa and Madagascar owe their great diversity to the enormous amount of area that they are found. Many species live in the most tropical conditions found it Western equatorial Africa in the countries of Nigeria, Gabon and the Congo (and many more). From there, they can be found in the hot and dry regions of equatorial East Africa and then continue through a huge variety of climates on down to the very tip of South Africa. There exist a tremendous number of species, but perhaps best known are the Angraecoids, that are both epiphytic and terrestrial. Many growers have seen the beautiful terrestrial ground orchids, Disa and Satyrium, found in South Africa. Madagascar also has an enormous wealth of orchids worthy of horticulture attention, we feel that some of these are without a doubt, the most beautiful of all orchids.
Temperature-- Since most of the members of this group, apart from a few exception like Aer. mystacidii and Ansellia africana, come from tropical region, they are best grown under intermediate condition. Although there are a few warm growers which come from near sea level areas, these also do well under theses intermediate temperatures. These temperatures will run from 55-65 degrees at night to 80-85 degree days. Today, one can easily check on the temperatures of the native area through the internet. A good differential of day-night temperature is welcome.
Light--Most of these species and hybrids appreciate a fair amount of light, These conditions would be very bright filtered light. It is true that some African species grow in full sun conditions. Growing your plants with too little light makes them too soft and leaves them open to disease. If you are an indoor grower, moving you plant outside for the summer growing season will be beneficial.
Humidity and Air Movement-- For the most part these are tropical orchids and will appreciate rather humid conditions especially in the summer months. Any that come from drier areas will not be damage by keeping the humidity rather high. If possible keep humidity in the 60-65 degree range especially if you give them higher light. While the humidity is high, it is best to provide good air movement to keep conditions clean and fresh. Exchange the air daily if growing in a humid greenhouse.
Water-- Most of the species and hybrids can be grown well as mounted plants and require very clean water so that there is no salt build up. It should be applied freely during the growing months. Mounts can be watered daily to simulate the natural conditions found in Africa and Madagascar. Most plants will do better with a more infrequent watering schedule in the cooler winter season. Aerangis species with large roots, like Aer. kotschyana and Aer. verdickii, must be dried out at this time. Give ample balanced forula fertilizer fairly often in the growing season and less frequent in the rather dormant winter season.
Potting-- Many of the Angraecoid species and hybrids will do best as mounted plants. This helps to avoid any root rot during the dormant season. If you grow in pots, you must keep the media fresh with annual potting. Do not let the mix get old or stay too wet, or you will lose good drainage and you will lose the roots. We like to mount on cork bark for the true epiphytes. For the potted varieties we us a rather coarse mix of fir bar with the occasion use of charcoal.