Picea glauca – White Spruce
Picea pungens glauca – Colorado Blue Spruce
Spruce trees are truly ubiquitous in central Alberta, and the epitome of tree species to many people. While I don’t share that view, I do appreciate their abundance in the city, as they give year round colour to our neighbourhoods, and truly make the urban forest seem like a forest. I would never plant a spruce tree in an average residential yard, because of their canopy density, the amount of shade they cast, and the huge footprint that the mature form requires. I much prefer pines to spruce, as pines allow you to see through the canopy. Spruce look great on the horizon, or framing a view. They have plenty of value in parks, natural areas, acreages, and properly positioned in large yards.
There are a variety of smaller cultivars available, which are more appropriate for smaller landscapes, such as Picea ‘Bakeri’, which only grows to about 12′ tall. White spruce are generally more narrow and less dense than blue spruce.
Many spruce trees find there way into yards when they come home with the kids on Arbor Day. People take the cute little saplings and plant them 6′ from their livingroom window, or deck, or fence, and watch them grow. By the time the kids leave home (if they leave home), the spruce is resting on the roof, pushing on the livingroom window, overtaking the front yard, and growing out onto the sidewalk. Just like the kids, the tree doesn’t stay cute! And very few people take the mature size of spruce trees into account when selecting a place in their yard to plant them. The other thing is, once a tree is mature, many people are reluctant to remove them, because they often provide a great deal of privacy to some part of the yard. At that point, some people seek to contain the tree, and have it shaped every 2-3 years. The tree then loses its natural form and, unless properly shaped, takes on a blob-like appearance that is often a bit garish in the landscape.
As with most tree species, it is important to plan out a suitable spot for it prior to planting, to avoid unnecessary or costly maintenance later on. Spruce can be nicely positioned on the NW corner of the back yard, which won’t shade the yard, will provide a nice-looking back-drop, and provide shelter from prevailing NW winds. Planting a spruce on the south side might be good for temperature-control during hot summer months, but don’t allow the heat and light from the sun to penetrate during winter.
A mature spruce takes up a lot of space, and it is difficult or impossible to grow a nice lawn under the tree, unless the spruce crown is raised up so high that the tree looks ridiculous. Other plants struggle under spruce trees as well. No wonder, its dark and dry under a thick tree. Plants need light and moisture to thrive. People mistakenly believe the only reason plants and grass won’t grow under the tree is because of the acidity of the soil. This isn’t correct. If it’s privacy you want, there are better trees to choose from, that won’t take up as much space, and will allow for mixed plantings in smaller landscapes.
We like to create shade gardens under mature spruce groves, particularly those of white spruce. Proper plant selection is key for the understory, but as long as trees and other plants all get what they need, the garden will do fine.
Part-shade to full sun.
For clearance pruning, anytime of year. Deadwood removal is best done in the winter months, as it is a dirty, dusty job, and the small twigs break off easily in the cold. You’ll also want to wear long-sleeved shirt for deadwooding, otherwise your arms will look pretty assaulted at the end of the day.
Most spruce pruning in residential yards consist of clearance (from a structure, driveway or sidewalk), width reduction on the lower half of the crown (as the tree encroaches on the yard), and deadwood removal on mature trees. Deadwood removal is purely esthetic, and really improves the look of a mature specimen, especially if it was placed in a very visible part of the yard or next to the street.
I prefer to shape from late summer onward, after the season’s growth flush is complete, and hardened off. Shaping in September gives a nice shape until the following June. If you make a nice shape in May, the tree will start looking “furry” again in June. If you really want to arrest the growth of the tree, pruning while the new growth is expanding works best, although we rarely do this. We prefer to let the crown expand a few inches after each re-shape.
(c) 2017 Shane LePage, Wild Rose Garden & Tree Service Inc., Red Deer, AB.