No person shall distribute an adulterated soil or plant amendment. A soil or plant amendment shall be deemed to be adulterated if:
it contains any deleterious or harmful agent in sufficient amount to render it injurious to beneficial plant, human, animal or aquatic life when applied in accordance with directions for use on the label, or if adequate warning statements and directions for use, which may be necessary to protect plant, human, animal or aquatic life are not shown upon the label;
if its composition falls below or differs from that which it is purported to possess by its labeling; or
if it contains unwanted crop or weed seed, or primary noxious or secondary noxious weed seed.