Opium poppy (Papaver somniferum), also called bread seed poppy and sometimes Turkish poppy or peony poppy, has been cultivated since around 3400 B.C.E. and has been used for both its medicinal and recreational drug qualities. The seeds of the plant, which do not contain significant amounts of the opiate substances, are legal to purchase, own and consume, although in recent years the DEA has attempted to outlaw--or at least deter--garden catalogs from selling the seed for planting in an effort to deter the propagation of an illegal substance.
While the flowers of poppies may be intoxicating to look at, it is the seed pod that follows the flower which contains a milky sap that holds the main ingredients found in opium: morphine, codeine and thebaine. These substances are listed as Schedule II substances by the DEA. Schedule II drugs are considered to have a high abuse potential which can lead to addiction but do have an accepted medical use. These drugs may not be dispensed or used without a physician's prescription and monitoring.
Schedule II drugs may not be manufactured, distributed, dispensed or possessed. The nature of a poppy plant is to produce its sap, which in turn contains many Schedule II narcotics. Penalties for possessing even a very small amount of Schedule II substances can lead a first time offender to a prison term of up to 5 years and fines of up to $1,000,000. Possessing a Schedule II substance with intent to manufacture (which includes growing) or distribute can lead to a prison term of up to 20 years.
Many growers believe they will not be prosecuted for growing a few plants. While it is true that law enforcement rarely interferes with a few plants in the garden for the purpose of creating seed or just for aesthetic value, in the eyes of the law, it is only the amount of time you spend in prison that changes. In addition, it is not merely the fresh garden plant that is illegal. The dried seed pods and dried stalks and leaves of the plants, sometimes called "poppy straw," are also illegal to possess.
While it is perfectly legal to possess poppy seeds for culinary purposes, it appears to be no defense when it comes to a reason to grow poppy plants. In addition, eating poppy seeds has been known to cause positive results in drug screens of otherwise clean individuals.