Myrtillocactus geometrizans
(This plant comes in a 3.5" pot. You will receive a very similar plant to the one in the picture. It may or may not be blooming at the time of your purchase. The plant is shipped in its pot to prevent any damage to the roots).
Myrtillocactus geometrizans is a blue highly branched columnar candelabra like tree cactus that creates a dense growth of stems growing closely together. In nature grows up to 4.5 m tall, with the crown reaching up to 5 m in width.
Flowers & fruit: Rather smaller (2.5-3.7 cm) in relation to stem, greenish white in March, that turn in very sweet, edible, dark red, oblong fruits 8-20 mm in diameter. Starts blooming when it is about 60 cm tall.
Some of the information in this description has been found at desert-tropicals.com, llifle.com and cactus-art.biz