I found some additional information on P. nudum:
http://www.ucmp.berkeley.edu/p...
I don't know where you live but this map shows the distribution of P. nudum in the U.S.:
http://www.efloras.org/object_... There are many wholesale nurseries in Florida that ship plants to garden centers and nurseries all over the country so I suppose the spores could have traveled in that manner and took up residence in the container with your Asparagus.
