Mylar is a patented trademark name for plastic sheet film made from polyethylene terephthalate, or PET. It comes in varying coatings and thicknesses. Mylar's mirror-like reflective quality helps light intensity for indoor gardens and greenhouses.
Buying and Installing Mylar
Well-appointed home and garden centers will carry Mylar rolls. A standard roll of Mylar film for garden use measures 48 or 55 inches wide. Length varies from 25 to 150 feet.
Standard thickness ranges from 1 ml to 4 ml. The thicker the Mylar, the easier it will be to handle. Both sides of the film should be metalized.
Install the Mylar around the garden, keeping the film at least six inches away from your plants so that reflectivity in the entire room is more intense. Cover walls, ceilings and even floors and table surfaces. Tack or tape the film directly to the surface.
Mylar is not inexpensive, therefore if you cannot cover every surface of a room, a good alternative is Mylar along with flat white paint, which also is strongly reflective, used on the walls and floor.
Mylar for indoor use also can be purchased in the form of a "grow tent," an enclosed space completely coated with reflective film.