How Long is the Colorado Growing Season?

Not particularly long and not the same every year! I love heirloom tomatoes and hubbard squash, but need to move to the tropics to guarantee them coming to maturity before the frost—and to get away from the bears who have similar tastes. Then, too, the early season can be plagued by a late freeze and the mid season by hail. Nevertheless, the best amongst us constantly have productive gardens, using indoor starts and appropriately sunny locations. I can grow arugula since it grows and bolts on me in a month, but perhaps I have to accept that I have two left, non-green thumbs!