This is early blooms....usually they flower late summer to mid fall....the color, form and stripings on the petals are just beautiful to look at.
Thank You for posting this: I have a blooming sized Dendrobium goldschmidtianum that I am expecting to flower soon....I am glad to see what to expect.
I'll post a pic of the whole plant. Where this thing flowered was being considered to be cut off. Then I said "nah!" its still green let it go. There are maybe 3-4 other blooms ready to go.
like my other plants, this has been outside since March. After acclimating it, I baked it in the sun for a few hours a day until the plant was turning purple and then put it in bright shade for the past few weeks.