The Grammatophyllums are medium-sized to very large orchids, including the Giant Orchid (Grammatophyllum speciosum), believed to be the largest orchid species in existence. Its pseudobulbs can grow to a length of 8 or more feet. Plants can develop into gigantic specimens weighing from several hundred pounds to a ton!

Grammatophyllum (Gram.) has 11 recognized species. The name is derived from the Greek words ‘gramma’ (letter) and ‘phyllon’ (leaf), referring to the dark markings in the flowers. This genus of epiphytes occurs in dense rainforest from Indo-China, to Indonesia, the Philippines, New Guinea, and the Southwest Pacific islands. The species produce several racemes, arising from the base of the pseudobulb, with many yellow-green to olive-green, waxy flowers with dark purplish-red marks.

As warm growing species, these orchids can flourish here in South Texas if they are given very bright light in the morning and late afternoon and a good soaking once or twice a week. The brighter the light that they have (to just short of burning), the more flowers they will produce.

As the plant begins to mature it produces a "nest" of roots around the base of the pseudobulbs. These act to catch leaves, small twigs, animal droppings, and other organic matter which gradually decompose and fertilize the plant in the process. Fertilize Grammatophyllums by placing several tablespoons of compost over the root nest or water with a diluted basic fertilizer such as Grow More 20-10-20 urea free every third watering.