The bread seed poppy (Papaver somniferum) is an annual flowering plant that produces attractive flowers. It is also called the opium poppy because the "sap" contained in the seed pods is used to make this illegal narcotic drug. Papaver somniferum prefers cooler temperatures, which makes fall the ideal time to plant seeds. If your winters are very cold (USDA zones seven and lower, or north of Oklahoma or Virginia), you can grow this plant indoors under lights. Lights are absolutely necessary because this poppy requires lots of light in order to produce flowers.
How to Grow Papaver Somniferum Indoors
Purchase seeds from a specialty catalog or the Internet. (See Resources.)
Fill 10-inch or larger nursery pots with a good quality potting mix with a neutral pH of around 7.0.
Scatter seeds sparsely on top of the soil and then barely cover them with a small amount of soil mix. Water thoroughly and then place your pots under lights for 12 hours each day. (See Tips.)
Spray your pots with a fine mist of water once every day and keep the soil moist but not soaking wet.
Thin plants to the strongest seedling per 10-inch pot when they are two inches tall or less. Poppies do not transplant well, so starting them in the pot where they will spend their lives is the best way to grow them.
Reduce the amount of water you give your plants when you begin to see flower buds forming. Also stop misting when this occurs.
Increase the amount of light plants receive to about 16 hours per day when buds begin to form. You can let the temperature go a little higher during blooming: daytime temperatures of 68 to 75 degrees Fahrenheit and nighttime temperatures of 35 to 55 degrees Fahrenheit are recommended.