Have a hanging pot of Lantana and it has black bean looking things growing out of the bottom drain holes. Was just repotted 2mo ago. Help
It sounds like the roots are extending out of the pot.
Lantana roots are knotted looking and have larger and smaller areas, it could appear bean like.
If it's just a few roots, you can root prune the plant; but if it is very root bound you may want to repot to 1 size larger pot-again!
Use a good quality potting soil.