The leaves of the poisonous autumn crocus (Colchicum autumnale L.) look totally different: they are thin, long and lanceolate and have no leaf stem, but grow from the stems that remain in the soil. The autumn crocus’s leaves are flexible, almost rubber-like, and, unlike wild garlic, do not break when fresh. These leaves have no clearly visible ribbed leaves, as opposed to wild garlic. They are difficult to almost impossible to grind between the fingers. The leaves of the autumn crocus are odourless. But beware: the penetrating garlic smell of earlier samples of real wild garlic might still stick to the fingers and can be misleading when sampling other leaves. Thus, always consider looking for other distinguishing features.
Three to four autumn crocus leaves can be enough to cause death when eaten. Colchicine, the cell toxin contained in the leaves, takes effect only after several hours. The first symptoms are nausea and vomiting, followed by diarrhoea. The toxin destroys intestinal, blood and bone marrow cells, which could end fatally after about two days.