Try a clear coating used by automotive industry. They have been using this type of finishes  for many years, under the toughest conditions possible, ( gravel roads, salted & sanded highways, winter blizzards, scorching sun, off road driving through jungles ) i can go on and on.  With great results.  I spray painted my boat with a C.I.L. auto paint 25 years ago still looks new. A lot of it is about the right preparation. I agree leave it green.
 May the wind always be in your sails ,
Lawrence from  LA VALJES