I am interested in planting a dwarf Colorado blue spruce in my yard (I live in Kirkland), but my landscaper said that blue spruce does not do well here. Is she correct? It is true that there aren’t any on the Great Plant Picks list.
According to local gardener and author Arthur Lee Jacobson, Picea pungens
f. glauca (Colorado blue spruce) is quite common in gardens here, but in
his opinion it does not have many assets beyond its striking color and
hardiness (North American Landscape Trees, Ten Speed Press, 1996). I
wonder if your landscaper has observed that it is susceptible to spruce
spider mites, aphids, and other pests and diseases. I see that it is
susceptible to Phytophthora, which is often a problem in our area. The
book Trees & Shrubs for Pacific Northwest Gardens by John and Carol
Grant (Timber Press, 1990) concurs that Colorado spruce is not the best
choice for our region because of pests and diseases. Newly planted trees
will also need regular watering for their first year, and if they do not
receive it, they are likely to suffer dieback or death. Here are links to
additional information from the Washington State University and the Urban Forests Ecosystems Institute SelecTree site.
Excerpt:
Pest & Disease: Susceptible to Aphids, Scales and Spider Mites, Oak Root
Rot, Phytophthora, Root Rot, Rust and Sooty Mold.
If you love the look of this tree, you could try growing it despite the
drawbacks, or you could look for other blue foliage conifers which may be
easier to grow here. Great Plant Picks mentions Abies pinsapo ‘Glauca,’
though this is not a dwarf tree.
You might want to search the Oregon State University Landscape Plants web
pages for additional information on any other trees you are considering
for your garden.