Nightshade in bloom. The flower will drop off and a green berry will develop, turning black when ripe. While not as poisonous as the deadly nightshade, unripen berries are toxic and will make adults very sick. There are cases death in small children after ingesting the berries. Ripe berries are edible and the entire plant if prepared properly, can be eaten. In Africa and China, in times of famine, black nightshade is gathered and used as an important food source. Relatives of the nightshade includes such plants as tomatoes and potatoes. As a side note, it is recommended that the eyes and green colored parts of potatoes be discarded before cooking as it contains toxins similar to the nightshade.