First time blooming.
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I bought this two years ago as a small three-bulb division. It reacted quite badly when I unpotted and mounted it on a piece of cork; it barely grew and even lost couple of leaves. I thought I might have killed this little guy.
But this year, all in sudden, it began to grow vigorously and the newest pseudobulb begin to swell up like a balloon and voila, a flower bud emerged! And it grew bigger and bigger and finally opened up yesterday.
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Now I am a happy man!
PS: Picture 1 and 2 are from yesterday when the bud began to open; 3 and 4 are taken today.