This is the link to the findings from the University of California Agriculture and Natural Resources Co-operative Extension on a handful of dragon fruit varieties. 

https://vric.ucdavis.edu/ucd-access/VC3%20workgroup/VegCropsPT_2016/05_Lobo_VegCropsPT2016.pdf

Rare Dragon fruit is all about education of growing dragon fruit we aim to share as many resources as we can on growing dragon fruit so you can make educated decisions on how you choose to grow your own fruit.

There are so many options and ways to grow there is no wrong or right it is what works best for the plants in your area. 

Please take a read and learn something new about dragon fruit and Pitaya