Q: I have three dwarf Alberta Spruce. Two of these have
developed three tops rather than one dominant.
How can I maintain or
them to keep the preferred "Christmas tree" shape with one main branch
rising from the top?
Thanks for your help.
Remove the 2 back to their base,
not just at the "outline" of the tree as they may sprout anew from the cut
and just thicken things up again.
Since the growing season is over there's no urgency to do this. However,
if, by doing this pruning, the trees' appearance may become a little
"compromised", I would wait until spring, when the new growing season is
upon us, to do the pruning.
This way, once you've pruned the competing tops
off, the new growth will help hide any odd-looking cuts you might have
needed to make sooner than if you pruned now and had to look at the plants