The white film has improved light transmission. Using white plastic film for greenhouses allows for maximum sunlight penetration. It absorbs heat, saving energy.
The films used on vegetable greenhouses typically come in light blue and white varieties. The light blue film absorbs light itself, which can help rapidly increase the temperature inside the greenhouse. However, light blue films have an issue with light transmission, filtering out some blue light that promotes photosynthesis, affecting the coloring of vegetables like tomatoes and peppers. The white film filters out red and red-orange light from the spectrum.