History of Mushroom Cultivation
The methods used to cultivate mushrooms today are very similar to those over 100 years ago.  Agaricus can fruit in the dark, but they do require some light to induce stable flushes of fruiting and to produce high yields.  An overhead source of incandescent or fluorescent light is sufficient.  It is uncertain how the pictured mushrooms growning in mines were lit; possibly using candlelight!

Photographs of Agaricus cultivation in a mine
Scotland, origin unknown, sometime during the late 19th/early 20th century


Photographs of Agaricus cultivation in Sheds
Traditional mushroom farm, Aberdeen, 2001