Some people prefer to start them indoors under lights, but be sure to start them in Peat Pellets, as poppies do not transplant well because they have very sensitive root systems and one very long Tap Root that can be damaged easily; killing the plant.
But once they sprout, you should put down some Slug Bait. Slugs love to eat tender, young seedlings. I suggest using SLUGGO because the active ingredient is iron phosphate, which is completely harmless to pets and animals, and remains even after it rains.
Poppies don’t need to be watered too often Maybe once or twice a week is fine. But when you do water, give it a nice soaking.
This will promote strong root growth. Poppies also like as much sun as possible. Put them in an open field where they will get a lot of sun.
Poppies will begin to bloom 10 to 12 weeks from the time you plant them. Their pedals will drop after about 48 to 72 hours. Then the pods will continue to grow for the next couple weeks. During this period, it’s very important not to water them unless absolutely necessary. Once pods turn a bluish tint with a white film on top, they are ready for harvest.