It is tough to develop crops within the Peruvian desert. The Chincha nonetheless managed it centuries in the past. Their trick even gave them good relations with the highly effective Incas.
https://www.spiegel.de/wissenschaft/mensch/peru-wie-ein-volk-durch-vogelkacke-reich-wurde-a-67082cb5-1830-4d97-9aea-09c1057b2b75#ref=rss