Mongolian Giant Sunflower (Helianthus annuus) 5 Rare Organic Heirloom Seeds Offering 5 Mongolian Giant Sunflower seeds, with near 100% germination rate. Harvested from non-GMO, organically grown Mongolian Giant Sunflowers, without the use of pesticides Grown and available all year from sunny south Florida Seed will arrive in a resealable bag.