Use an old, non-functioning refrigerator to provide a self-contained environment for plants. Called a refrigerator grow box, use it to start plants or vegetables early in the season or extend the growing season of existing plants. People with limited or no gardening space use this method to grow their favorite plants with soil or hydroponics, and also to recycle unused equipment. The refrigerator must seal tightly though, allowing you to control the internal environment.
Stand the refrigerator in a well-ventilated area and drain the freon. Remove the coils and air compressor. Remove the main power cord and any wiring. Also remove all racks and shelves from inside, except one you will use for your plants. Scrub the inside well with a non-abrasive cleaner.
Select an appropriate position for the grow light and drill a hole in the back of the refrigerator, just wide enough for the cord to go through.
Attach the grow light inside the refrigerator with a cable or chains so it hangs over the shelf, and extend the power cord through the drilled hole in the back.
Determine the size of the exhaust fan and cut a hole the same size in the back of the refrigerator. Slide the fan into the hole so its front faces the interior of the refrigerator and its back sticks out. Seal any gaps around the fan with silicone caulk.
Cut another hole in the back of the refrigerator, the same size as the one made earlier for the exhaust fan. Position this second hole just below the exhaust fan. This hole offsets the exhaust fan to allow proper ventilation inside the refrigerator, without unnecessary exposure to light. Slide a second fan into the lower hole, and seal the gaps around it with silicone caulk.
Replace the rack inside the refrigerator. Fill seed starter flat or small pots with potting soil and seeds, and place on the rack. Extend the power cords for the light and fans into a power outlet and turn on.