Hey, do you have this plant? If so, how big does a baby blue spruce grow?
I think this baby blue spruce is a slow grower, and it might only grow to be about 15 to 20 feet tall when it's fully grown.
I also have a baby blue spruce, and based on what my plant gives me, it can grow to be as tall 23 feet and 10 feet wide.
I'm sorry to not have the answer to your question, but I think the USDA zone and care depend on the plant. I wish I could help more, but I didn't find the right answer. I know that most of the plants near my house can grow to be up to 25 feet tall, though!