Answer: You would definitely want to select a named cultivar that matures to a size that fits the space where you will be planting. According to the Monrovia online descriptions, Fat Albert is by far the smaller of the two: Slow grower to 10 to 15 feet tall, 10 to 12 feet wide. Grafted. Since it is grafted, the mature size should be very consistent from plant to plant. The way to tell the difference is to purchase a plant that is labeled with the complete botanical name: Picea pungens glauca 'Fat Albert.' There may be some variations in the trade between these plants as there are so many different spruces on the market and sometimes there is variation from supplier to supplier. However, with the Monrovia plant the mature size should be consistent with the Monrovia description.
Sometimes the word specimen can be used to mean a tree that is highlighted in the landscape, other times it can simply mean an individual tree. With evergreens, a younger and thus smaller sized tree will usually be less expensive to purchase than one that is larger and more mature. Perhaps this is what your landscaper meant.
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