Wall o water results after 4 days of use

A week ago, I received my wall of water which are plastic things that can get filled up with water to create a wall of water around the plant, and this is supposed to prevent the effect of frosts as well as extend the season. The biggest benefit is that it is supposed to heat the soil which is an important factor in a northern climate. Let's see how it helps some of my plants. These pictures are taken 4 days apart.

Gunnera division. They are slow growing anyways so not much change. I don't really understand why this uploader rotates pictures sometimes, but it does. 

The temperatures have ranged around 40F-60F and mostly sunny on all of these days since the wall o waters were set up.

Big gunnera. Looks like I might not be able to keep the wall o water on too much longer here.

 Musa basjoo 1 These are showing more noticeable changes since bananas generally react to warmer temperatures much faster.

Musa basjoo 2

I'm also using it on some of my hot peppers, and they seem to be doing better than the ones outside the wall o waters since we still get very cold nights in the upper 30s.