Re: What environment (warmth, light) promotes mold growth on bread?

Most molds require some water, some nutrients, a warm enough temperature, 
and an environment without a lot of competition from bacteria to grow 
really well.  Most molds do not require light to grow because they do not 
use photosynthesis like plants do.  They will also grow over a very wide 
range of temperatures.  At cooler temperatures they will still grow, but 
will take longer than at warmer temperatures.  

To get really good mold growth on bread, choose a bread that does not 
contain preservates like propionates.  These are added to the bread 
specifically to inhibit spoilage microorganisms such as molds.  A fresh 
loaf of bakery or home-made bread usually work very well.  Put the bread in 
a plastic bag along with about 10 milliters of water and a light dusting of 
soil.  Close the bag enough to retain the moisture and put it in a drawer 
or other dark area.  In a few days you should be able to see some very good 
mold growth.