What is the largest orchid species in the world by size?

The tiger orchid, Grammatophyllum speciosum, is generally regarded as the largest orchid species by overall plant size. It is also called the giant orchid, sugar cane orchid, or queen of the orchids. The name “tiger orchid” refers to its yellow flowers marked with dark reddish-brown spots.

This giant epiphytic orchid grows on trees or, occasionally, on rocks across parts of Southeast Asia and the western Pacific. Its long, cane-like pseudobulbs can reach about 2.5 meters, while mature plants may form enormous clusters weighing hundreds of kilograms or even more than a tonne.

Its flower spikes can grow to roughly 3 meters and carry many blossoms. The plant typically flowers only once every two to four years, but a flowering display can last for weeks. “Largest orchid” can mean different things—plant mass, pseudobulb length, flower size, or inflorescence length—but Grammatophyllum speciosum is the standard answer for overall size.