My asparagus was started with crowns and took 3 years to establish.
All well until we had a fire came through. Most plants escaped damage, so I moved them closer to the house. Another 2 years to come back to harvesting size stalks. In the meantime, through human agency and the birds several plants have come up elsewhere. . . Since I didn't see them until they were at the fern stage, no idea yet if maturity has been reached. If plants are where they aren't wanted then they are "Weeds" and given the transplanting experience, I don't think they should be too hard to eradicate. Best of Luck.