Petunia is a genus in the family Solanaceae, subfamily Petunioideae. Well known members of Solanaceae in other subfamilies include tobacco (Nicotianoideae), and the cape gooseberry, tomato, potato, deadly nightshades and chili pepper (Solanoideae). Some botanists place the plants of the genus Calibrachoa in the genus Petunia,but this is not accepted by others.Petchoa is a hybrid genus derived from crossing the genetically similar Calibrachoa and Petunia.