This works much better than Vet wrap.
We do this , Then simply just tye a tail bag over it. Create a Horse Tail Wrap From a Bedsheet
then at the end make a mark at where ur tail was and you can keep track at how much it has grown.
I had something like this. I found it to be more of a pain in the butt than anything else, and it wouldn't say on long either (and that was when Vega was in a single paddock and didn't have enough room to run or anything)
It is a good idea though :) Maybe I'll try this in the summer or something.