Trimming Alberta Spruce

(Question)

Hello!

We have bought my mother-in-law’s house recently, sadly she has let her garden go for the last few years and everything is horribly overgrown. There are two giant evergreen trees on either side of the walk to the door that are growing out of control, the bottoms look a little bit dead but my husband is sentimentally attached to these trees as he had planted them as a kid. They don’t look very healthy, the needles are only located right at the tips of the branches like little poufs. The one of the right side in the photo had a huge bush behind it was growing into it & when i trimmed the bush away there were huge bald patched where the poor thing must have been starved for light. My questions are really, what types of trees are these and how can i trim them back (without making things worse) so they are a more manageable size?

Thank you kindly!

(Answer)

Thank you for contacting the Toronto Master Gardeners.

The trees in your photo appear to be very healthy Dwarf Alberta Spruce, Picea glauca ‘Conica’. These evergreens do best in full sun to partial shade and prefer average to moist soil. These trees posses a dense needle pattern and a tight densely packed growth habit, which gives these trees a “fuzzy” appearance.

Don’t let the name fool you, even though Dwarf Alberta Spruce grow at a slow rate- growing just 2-4″ per year. Under ideal conditions these tress can grow to a maximum of 7-10’ wide and 10-12’tall and can be expected to live for 50 years.

These evergreens should be pruned in early spring, when you first notice the new growth appear. It is recommended to only trim back the new growth of the current season. Pinch off the tips of lateral branches to maintain the size of the tree’s height or width by cutting away just the end 1/2 to 1 inch of new growth. By trimming back the new growth that appears on the side branches each year you may keep them from getting much wider than they are now.

Avoid pruning the dwarf spruce back beyond where the needles grow, otherwise the plant may not produce side shoots to fill in the space with fresh growth. If pruning this far into the tree is necessary, then cut the lateral branch cleanly away from the trunk. Too much pruning on dwarf spruce trees can cause the needles to turn brown or die back.

Prune out any dead or diseased branches as well as branches that appear to be rubbing by tracing the affected side branches back to where they extend from a lateral branch. Cut the damaged branch off the tree by making a cut that runs parallel to the lateral branch and just 1/4 to 1/2 inch from the lateral branch.

Gook Luck with your trees.