Q: How about artificially colored mulches?
A: We have tested mulches of various colors, as well as the chemicals themselves that are used to color the mulches. The chemicals in our tests, at the concentrations used, did not inhibit the artillery fungus.
Colored mulches appeared to very slightly, but only temporarily, inhibit the artillery fungus. We attribute this to the colored mulches being slightly more water repellent and therefore remain drier than the non-colored mulches, at least at first. As the colors faded due to rain and sunlight, the artillery fungus moved right.