Q.Christmas Tree
I have a Douglas fir that needs trimming. How and when do I trim it back and is there a way to stop it’s upward growth? It currently has its spring buds.

Certified GKH Gardening Expert
It isn't a good idea to do so. They can fall victim to disease, and their appearance is permanently altered (usually never for the good of the tree). It can also lead to an unstable tree prone to falling apart and cracking.
Unfortunately, these are very large trees and should be placed in a spot that will allow for this. You may end up needing to remove the tree.
Here are some articles that will help:
https://www.gardeningknowhow.com/ornamental/trees/fir/douglas-fir-tree-care.htm