- You Will Get 500 Seeds Of Lychnis Chalcedonica Jerusalem Cross Flower Seeds. - Sunlight: Full Sun. - Watering: Light. - This is for 500 seeds this is Lychnis Chalcedonica this is known as the Maltese Cross or also the Jerusalem Cross this is known as a Perennial in zone 3-10 it grows to be about 30" tall. - These like full sun to part shade and will come back year after year for you. - This is a old heirloom flower if you want humming birds they love this flower.