300 Persian White Strain Poppy Seeds (Papaver Somniferum) Produces large bulbs and highest poppy yield. Growing Instructions Transplant seedlings into your garden after all danger of frost. Final spacing of plants should be 8" - 18", depending upon variety. Poppies grow quickly, and will bloom in early to mid summer For best results, add a general purpose fertilizer once a month. Mulch around plants to keep the weeds down, and for an attractive appearance. Water only during extended dry periods. Deadhead flowers to promote new blooms. Do not do this if you plan on harvesting the seeds. To harvest the seeds, allow the flower to die and dry. Snip off seed pods and lay the out on a flat surface to completely dry. Separate the seeds from the seed pod, and store for later use.