something that nourishes one's artistic skill
Idiomatic expression likening experiences or knowledge to fertilizer for one's art. Often used when an artist draws inspiration from life events, other arts, or study.
See also: 肥やし (こやし)
Encounters during his travels became nourishment for his art.
My teacher often said that reading is fertilizer for one's art.
Compound of 芸 (art, skill) + の (possessive particle) + 肥やし (fertilizer). The expression figuratively compares experiences that enrich one's art to fertilizer that nourishes plants.