I agree with Mass on this. When you asked in the chat about greenhouses your grow rack is not what I thought you were talking about. I have one of those and gave up using the plastic for anything outside. It was no help in creating a microclimate outside and was only good for a windbreak. I ended up just using the rack as a place to put plants out on the porch for the summer.
Keep it inside where you can create a nice enclosed microclimate for your plants.