Each raceme can grow to a height of 3m, bearing up to eighty flowers, each 10 cm wide. The flowers are yellow colored with maroon or dark red spots. These flowers are remarkable, since the lowest flowers have no lip and these flowers function as osmophores for the entire inflorescence and continue to emit chemical scent to attract pollinators as flowers open in succession. It blooms only once every two to four years. This orchid can, however, remain in bloom for up to two months.
