[3] Due to his good relations with the royal family, particularly the Queen, he was in the early 1770s, contacted by Frantz Heinrich Müller (1773–1801), a pharmacist and mineralogist who was setting up a porcelain factory.

This led to the foundation of the Royal Danish Porcelain Factory in 1775, with the King as a co-owner, Queen Juliana Maria as a protector and Holm as its first director-in-chief.

The first volume was not published until 1790, and the second posthumously in 1796, but the work relies on the studies he conducted during the two years he spent in Aarhus after leaving Sorø Academy and prior to his employment with the Danish Postal Services.

In Aarhus, Holmskiold had observed and documented the fungi he found and he also commissioned artist Johann Adolph Neander (1742-1766) to make detailed full-scale drawings of the specimens he collected and described.

[7] Holmskjold's initial engagement with the postal services was most likely a fairly easy task which left him with sufficient time to work on his study of fungi.

[11] In 1768, shortly after his appointment as general director of the Postal Services, Holmskiold built a country house on the shore of Lake Bagsværd in Frederiksdal north of Copenhagen.

[14][15] In 1782, the year after his ennoblement, he commissioned the architect Joseph Guione to build him a new and larger country house on a tract of land at the southern tip of Lake Bagsværd.

The Aldershvile estate was subsequently sold to Adolph Ribbing (1765–1843), a Swedish count who had been exiled for his involvement in the murder of King Gustav III of Sweden.