which fertilizer is best for newly planted tree(1.5m), and how often apply?
Christmas Trees. Nordmann Fir
Certified GKH Gardening Expert
These trees will rarely need fertilization. They can draw enough from its environment. Overfertilization can kill them. This article is for the closest relative of this tree, and will have the same care requirements: https://www.gardeningknowhow.com/ornamental/trees/fir/balsam-fir-tree-care.htm