Ha, I have not been here in an age and there is my photo, what do you know! I used the different kinds of cold frames for different purposes. The transparent ones and hoops are great for wind protection, capturing more heat from the sun, and warming the soil quicker in spring. They really speed things along in the spring and summer for sure. Here in zone 3, I use wood frames lined with thick insulation to keep things alive and growing far into the winter. And yes, I use the most cold hardy varieties of the the most cold hardy vegetables. I just find it a challenge to see what I can keep going when it drops to minus 25, which it does here.