I have some planted under a Mesquite tree. They are crawling up the trunk. I would say easter exposure with afternoon shade or filtered light.

It's a pretty easy grower actually. Just make sure the soil drains reasonably well and give it extra water in summer.

I know people that have fruited them here. I just planted mine a year ago and it needs to get bigger (originally from cuts).

Better know here as Pitahaya or Pitaya.

I've seen a couple of large ones in the barrio in Glendale

I have some growing in Queen Creek, they are on their third year in the ground. They are either growing under an orange tree or under a lattice for shade, they do get sunburned if left in full sun and they do require more water than a regular cactus. Mine have required very little supplemental feeding. The only one to bloom for me so far was my UNself fertile one, so of course HUGE blooms with no fruit, maybe this fall or next spring I'll finally get some flowers and fruit. If you're ordering from somewhere, be sure you get a self fertile variety!

Good luck,
Kevin

Does anyone know of a nursery in Phoenix area where I could purchase Hylocereus Undatus (Pitaya or Dragon Fruit)?

I've seen them occasionally at TropicaMango nursery.
Looks like they've got a new website and a new name (link below).
Also, there's the Arizona Chapter of the California Rare Fruit Growers. They have monthly meetings that I used to attend, good group of people that really know their stuff. Several of them grow dragon fruit. There's a tropical fruit demonstration garden at the county extension office, it used to have dragon fruit growing there as well. Their website is: http://www.azrfg.com/

Kevin

Here is a link that might be useful: Tropica Mango

They are more tropical than most cactus and do prefer richer soil and more water, although they will tolerate dryness and poor soil. I have found that they like to climb and will bloom when they reach the top of the trellis and *hang* down over it-must stimulate some hormone that says "bloom now" lol. Some growers will create umbrella type trellis' for that purpose. They would need protection in phx areas from sunburn, perhaps filtered light since they are used to growing up trees.

whats it taste like or is it sweet

Yeah, Alex's Tropica Mango nursery has bunches. The plant takes a hit when the temp. is 110 and higher so shade or filtered light is best during the hottest months, otherwise will take full sun the rest of the year. I have mine climbing a palo verde tree and water about once a week and planted in well draining cactus mix with lots of sand. Native plants receive 80inches of water a year so do take much more water than desert cactus. They taste wonderful too. Best if eaten after dinner or as a stand alone snack, the taste resembles watermelon. However if you eat it with or after something sweet it will taste more like water. There is a guy in Mesa that has dug up all his tropical plants and converted his whole yard to different kinds of pitahaya and they are doing really well.

Here is a link that might be useful: Alex's Tropica Mango Nursery

Some Home Depot Garden department carry this plant not all year around and just a few of them