Hi Merbs and yes I understand your dislike of polythene. With fleece however, the advantages are just immense!
Yes light is a factor, and why I use it rarely in the dark days of autumn (from now!) and mostly lay it over from the Equinox until first hot weather.
For autumn/winter I prefer mesh, less warm but stronger and protects from wind. And I cover v few crops then.
In the UK there appear to be only 2 weight options now, 17gsm which is hopelessly flimsy, and 30gsm which is almost too thick. There used to be 25gsm, the best in my experience.
