Cold frames are small open-bottom covers used to shield plants and seedlings from harsh weather. They are typically made of wood or aluminum frames with glass or rigid plastic covers and sides. Flexible plastic budget models are also available.
Some cold frames may be too lightweight for windy locations. Be sure to properly anchor the cold frame to the ground or structure.
The heat from a low wattage incandescent light bulb running inside a sealed cold frame and can prevent overnight frost.