self-sown

adjective

1. sown by itself, or without human or animal agency, as of a plant grown from seeds dropped from another plant.
2. sown by any agency other than humans, as of a plant grown from seeds scattered by birds or the wind.

verb (used without object), self-sowed, self-sown or self-sowed, self-sow·ing. Botany.

1. to sow or propagate itself naturally from seeds that have been dropped.

adjective

1. (of plants) growing from seed dispersed by any means other than by the agency of man or animalsAlso: self-seeded