Abstract: A mechanically strong doped polymer sheeting--high-density polyethylene (HDPE) film--that provides excellent durability, high-maintenance and photo-transforming properties for covering hotbeds and greenhouses is comprised of: a light-transforming additive based on yttrium-europium oxysulfide; a light-stabilizing agent based on polyaminosuccinate; and a polymer resin used to form the high-density polyethylene 6-mil film. A preferred embodiment includes following composition and ratios: yttrium-europium oxysulfide content is 0.05-0.5% by weight; polyaminosuccinate content is 0.1-1% by weight; the ratio of yttrium-europium oxysulfide to polyaminosuccinate ranges from 0.5:1 to 1:2; and high-density polyethylene content is over 98.5% by weight according to above percentage of the additives. The doped polymer sheeting, HDPE film, for instance, can be fabricated efficiently and compactly packaged making it suitable for mass distribution.