The generic name Abete del Colorado indicates a genus that has about ten species of evergreen trees, originating in North America; the growth of these trees is very slow, the adult specimens can reach 15-20 meters in height, although generally in the gardens they remain below 3-4 meters; there are many varieties with dwarf growth, which reach 150-200 cm in height or variety with pendulous or convoluted habit: for example P. p. glauca pendula has a prostrate habit and reaches 60-80 cm in height, widening even a few meters on the ground. The stem is erect, with dark bark, often very fissured; the branches are rigid, horizontal to the ground; generally the crown assumes conical or pyramidal shape, with dense ramifications; the oldest branches tend to lower the apices towards the ground over the years. The foliage is needle-like, 2-4 cm long, stiff and sharp, green-gray in color, tending to blue. These are dioecious trees, so only the female specimens produce the small brown pine cones, which grow pendulous, inserted on the lower part of the branch.
The trees of Picea pungens are cultivated in a sunny place, or even partially shaded; they do not fear the cold and can withstand very harsh temperatures without problems; It is more likely that they will have a stunted development in areas with a torrid and dry summer climate. Many varieties of picea pungens they are also suitable for gardens of limited dimensions, given the slow development, which generally does not exceed 2-4 meters in height.
This plant is also sometimes used in rock gardens to expand the variety of species and to play with particular color effects thanks to its beautiful and fascinating crown.
They fear very prolonged drought, so it is advisable to water the young specimens during the summer months, but only when the soil is well dry. Adult specimens can withstand short periods of drought, but it is good to check the soil if the summer season is not rainy. While they are conifers with an excellent ability to manage water reserves, it is also true that they are not very suitable for extremely hot and dry environments in which they suffer a lot.
Speaking of soil and substratum, the picea pungens prefer soft, fresh and deep soils, devoid of water stagnations but fairly wet, with a slightly acid ph. These plants fear the excessive presence of limestone in the ground but apart from these indications they have no other great requirements or limitations. This plant in Italy is present only as an ornamental plant. As for the climate, it prefers sunny and mountainous areas, with rather rainy summers. La Picea pungens suffers, however, when it finds itself having to face too cold and freezing temperatures. It can in fact withstand a minimum temperature of - 10 degrees.
The multiplication takes place by seed in spring, placing the seeds in a mixture of peat and sand in equal parts, to keep it fairly moist until germination; during the summer months it is also possible to practice semi-woody cuttings even if more difficult than hardwood cuttings.
Colorado Spruce - Picea pungens: Pests and diseases
Particular attention must be paid to the diseases that this species can develop. The plants of colorado fir they fear the attack of aphids and mites, especially when they are in areas outside their natural habitat. They can be subjected, especially in the areas of origin, to strong attacks by xylophagous insects.