That's what I'm talking about, Marilyn. If you're inexperienced, asking local gardeners and nursery people about where to plant something is a great way to go. That doesn't necessarily include the nice - but not necessarily knowledgeable - folks who work in the HD and Lowe's garden centers who more often than not can't tell you any more than what the tag does. Your local County Extension service might have Master Gardeners available to consult, too. A great, free resource.
Your location is a good example of why not to generalize terms like "Full Sun". You have clear air and you're at high altitude, right? So your sun is very strong at this time of year. On the other hand, your nights cool off quite a lot which can slow your plants down. Your hardiness zone might be 4, or 5, or 6 depending on if you're up the mountain or down in the valley and the way your garden faces. Your growing season is pretty short. So if I were you and bought a plant that said "Full Sun" on the label, I'd find it the warmest, sunniest spot I could even if it has 8 or 9 hours of sun per day. IF you're growing fruits or veggies, they need the most solar energy you can give them to produce and dependably mature a crop. South-facing side of a building will give a longer season than the north side because it won't get blasted by late snow or nipped by early frost. Even your flowering plants will do better, the more sun you can give them.
I lived in Utah for 20yr. before moving to FL and my kids still live there, very familiar with snow in late May and frost in early September. My daughter's garden in Salt Lake is zone 5 in the front - north side of the house - and zone 6 in the back yard that faces south and is protected from the NW wind. She has trees, and so do both her neighbors, so "Full Sun" in her garden is a max of about 4 hours, but her perennials bloom and grow beautifully. Just the ones in the front yard start a month or so later and finish earlier than the back yard. This goes back to generalizing about zones, too.
