In the last couple of weeks my white pitaya (dragonfruit) has gone from having a small bud to an enormous one that's just about to flower.  I'm thinking it will be tomorrow since it's already almost 5:00pm here:

 

Very nice i wish i could grow one good luck!

Nice, thanks got sharing. I have three varieties, how big do they have
to get before blooming.

Beautiful!  Rumor has it the plant has to weigh over 10 lbs before flowering starts.

Looks otherworldly...amazing! Heard they taste pretty good too!

Geez, they need to be 10 lbs to flower.  I've got a bunch of "Dark Star" dragonfruit going but they are only a couple years old so at this rate it could take years.

Here's another pic...

 

I've got a paint brush ready to try to hand pollinate, but with only a single flower, not sure how well it will work!

Can you post a pic of the entire plant?

Update just an hour or two after the last pics and just beautiful!  I already hand pollinated and will do again in a few hours and again in the morning, just to give it my best shot.:

 



   

such a beauty!
You can pollinate with brush, even if only one flower.

Some experts don't believe there are many varieties that are self-fertile but I've had success with some which I pollinated with their own pollen.  The fruit might be larger if cross-pollinated and, perhaps, success would be higher.  If you have enough flowers opening it's probably best to mix pollen and cross-pollinate.  I've had plants bloom when smaller than 10 pounds and one that finally bloomed for the first time this year and it was probably already 15-20 pounds last year.  I am probably going to build a greenhouse for my collection since they get too much freeze damage here.

Such a beauty.
Is that three plants or a single plant?
I started some cuttings this winter that I got from a generous member.
I'm wondering if it could winter in the garage at 45 degrees or under the grow lights in my cellar?
Vito

There are a total of 4 Pitaya growing up the post.  All pics, except the one in Post #10, are of a single Pitaya.

Thank you Figaro
Vito

Quick update, and I apologize for not having pic's... 

My hand-pollination of the single pitaya flower was successful and absolutely delicious!  It was the first time I've tasted a dragonfruit.   It was the white-fleshed variety which I had heard were pretty bland-tasting.  This one  was very sweet and tasted kind of like a cross between a banana and a papaya with a texture  more like a  kiwi.  I only ate about 1/4 of it and froze the rest for smoothies.  I'm looking forward to a lot more, but so far, no more flowers on any of the DF's. :(

PITAYA
                 

Looks delicious. I had my first one a couple months ago and I am hooked. Bought 6 starter plants from wellspring but they are 3 " tall so I will still be buying them for awhile. :).