I want to put this young boojum tree in bigger pot. What is best soil or soil mix for this young tree?
I would use a cactus potting mix for this plant.
Here is a link with more information.
https://www.gardeningknowhow.com/ornamental/cacti-succulents/scgen/cactus-potting-soil.htm
When is the best time to transplant my Boojum tree from a pot to the yard?
March would be a suitable time to do so. This article will give you more information on the plant: https://www.gardeningknowhow.com/ornamental/cacti-succulents/boojum-tree/boojum-tree-care.htm
We have a boojum tree that is approximately 10yrs. old & is approximately 20' tall.....photos attached. We live in Congress, Arizona, on SR-89, near Wickenburg. Our Boojum is the ONLY one in our subdivision!! Thanks Very Much, Robert C. & Ruth A. Thomas
I found two different sources that said NEVER prune a boojum tree! Considering their rarity and protected status in the wild I would heed that advice. Plus, they are very expensive.
http://www.public.asu.edu/~camartin/plants/Plant%20html%20files/fouquieriacoluminaris.html
https://arboretum.arizona.edu/sites/arboretum.arizona.edu/files/Boojum%20Care%20Website.pdf
https://www.gardeningknowhow.com/search?q=trimming%20a%20boojum%20tree