Disseminated without the intervention of human or animal agency; in common usage, sown by any agency other than man.
The Century Dictionary (Public Domain)
Use "self-sown" in a sentence
"Dead hedges of olive prunings were woven along the tops of the walls, and self-sown figs grew from between the stones."
"Flanking the path (which varies in width along the meandering nine-block route now open, up to West 20th Street) are planting beds meant to evoke the lush, self-sown greenery that thrived on the High Line during its three decades of desuetude."
"Fields of self-sown wheat and vines were growing there; also, there were trees known as maple, and they took specimens of all of them."