I enjoyed your post having recently bought a greenhouse myself. Actually it’s quite a small one for my balcony and I am slightly dubious as to its quality! On casual observation, it doesn’t seem any warmer in the greenhouse than outside, but perhaps this isn’t necessary if the goal is just to avoid frost.

It also came with a mesh style keep-warm jacket thing but it doesn’t instinctively seem that it would make much difference. Any ideas? I am currently growing some lettuce and salad leaves inside which I was hoping to transplant out. I also have some kale but hoping that that will be ok out in the elements.