Avoid overwatering which leads to the demise of many more orchids than underwatering. Constant wetness will cause the roots to rot, which leaves the plant without a means for taking up nourishment which then causes the leaves to droop and will eventually kill the plant. The classic advice is to water the day before the plant dries out. If you have to let the plant go dry to figure out what a dry plant weighs, it will not kill the plant and will make you a better grower. Another measure is to use the pencil trick (the point of a sharpened pencil, when inserted into the medium, will darken with moisture if the plant has enough water). And, there's always the old standby - put your finger in the mix. If it feels wet, it is wet. If you aren't sure whether it is time to water, wait one more day.
Disa is a genus of beautiful plants with rather triangular flowers, often red. They require VERY different care than other types of orchids, so it's easy to kill them if you don't know what you're doing. In particular, they like it wet and should never dry out. The best-known Disa is Disa uniflora, which in South Africa is known as the Pride of Table Mountain.
For some of you your 1 year subscription has run out. Please check the subscribers list to see where you stand. I hope to hear from you soon! Thanks to all for making this so much easier! The subscription system of $10 per year has been a great idea and has helped quite a bit as I have been able to obtain a lot of new books and reference materiasl. New references though, are now becoming available and I need to have more funds to purchase them. I only use any income from this site to purchase books or pay internet costs. Not a penny goes into my pocket. If you want to keep this site with the most up to date references then please send in your subscription!!! Today is the day! We need your help! All you in other countries than the US please help as well. You are about two-thirds of the users but send in only 5% of the total subscriptions. Please send a check or international money order to
This site is compiled from photos collected from growers or photo collectors around the world and I rely on them to try to be sure of their identification. As we all know, however, many plants are mislabeled and growers and collectors can't know all species in every genera, so please be advised that to the best of our knowledge the following ID's are correct. I have hundreds of references, thanks to you all, but often many species are not well represented. I try to the best of my capabilities to be correct but as the adage goes, "To err is human". Many species herewith have been scrutinized by taxonomic experts and will be correct, but this may not be true of all the species described. If you have any questions as to the veracity of any species described in this encyclopedia please e-mail me, Jay Pfahl, at firstname.lastname@example.org and we will work at correcting the mistake. As to the text it is compiled by culling notes from hundreds of books and publications [See Bibliography and source books] but it too can be wrong in part due to my mistake or in the often conflicting reports on various orchids.
Epiphytic orchids, those that grow upon a support, have modified aerial roots that can sometimes be a few meters long. In the older parts of the roots, a modified spongy epidermis, called a velamen, has the function of absorbing humidity. It is made of dead cells and can have a silvery-grey, white or brown appearance. In some orchids, the velamen includes spongy and fibrous bodies near the passage cells, called tilosomes.
Orchid stems are also specialized into what are called pseudobulbs. These are basically expanded stems that allow the plant to store excess water and food. The roots of epiphytic (tree-dwelling) orchids have a special outer layer of dead cells called velamen. Because orchids metabolize slowly in order to not outpace their resources, the roots also absorb slowly, meaning that they need help catching water as it passes by. The velamen cells catch and fill with water as it passes by so that the true root (the core of the root structure) has ample time to access as much water as it can. Velamen is silver-white in color, but becomes transparent when wet, so that when the root is wet it turns green as you are able to see through to the inner structures of the root that contain chlorophyll.
Catasetum orchids, along with the other members of the Catasetum alliance, have big, thick pseudobulbs with an attractive fan of thin leaves along their length. The flowers can be very showy, but are unisexual, so that male and female flowers look different. Lighting affects which kind appears. They need a dry rest after flowering when the leaves drop.
You can readily buy Paphiopedilum at fancy grocery stores, and if you can’t find them, find a fancier store where women shop with little dogs in their bag! While these types of flowers come in girlie soft pink, eye-catching yellow, innocent white and other soft colors, many of them are dark red, brown and green with hairy and warty petals. The infamous Paphiopedilum sanderianum from Borneo has lateral sepals (the side petals) that can hang down 3 feet (1 meter) long! This highly sought-after plant can cost hundreds of dollars. But there are plenty of wonderful Paphiopedilum plants out there that don’t cost an arm and a leg. Learn more about Paphiopedilum orchids.
Orchids of all types have also often been sought by collectors of both species and hybrids. Many hundreds of societies and clubs worldwide have been established. These can be small, local clubs, or larger, national organisations such as the American Orchid Society. Both serve to encourage cultivation and collection of orchids, but some go further by concentrating on conservation or research.