Dendrobium crumenatum

Dendrobium crumenatum produces upright, sympodial, pseudobulbs 300-700 mm in sigfig=1 abbr=on long and 8-12 mm in sigfig=2 abbr=on wide that are swollen at the first three or four lower nodes. The middle portion of the pseudobulb has two rows of leathery, oblong to egg-shaped leaves 50-80 mm in sigfig=1 abbr=on long and 10-20 mm in sigfig=2 abbr=on wide. Top portion of the pseudobulb bears pure white flowers 30-40 mm in sigfig=1 abbr=on long and wide. The dorsal sepal and petals are 15-18 mm in sigfig=1 abbr=on long and 5-7 mm in sigfig=1 abbr=on wide, the lateral sepals slightly longer and wider. The labellum is 20-24 mm in sigfig=1 abbr=on long and 13-15 mm in sigfig=1 abbr=on wide with three lobes. The side lobes are erect and the middle lobe is rounded with five yellow ridges. Flowering is sporadic but is triggered nine days after a sudden drop in temperature of at least 5.5 °C, usually as a result of rain, although the same effect can be artificially created. The flowers are fragrant, but the scent lasts only for one day. Joseph Arditti describes the flowering as "gregarious". All the flower buds in a geographic area will bloom on the same day, for exactly one day, none early,