Helianthus annuus, With the Largest Sunflower Seeds (Probably) - So when you want it all, Go to Pikes Peak! This is the sunflower that sunflowers look up to —Not just large golden flowers or a big, thick, sturdy stem, This Sun flower’s ‘Party Piece’ is offering the largest sunflower seeds in the world. Ginormous seed heads house seeds as large as THREE cm LONG—the biggest we’ve ever seen. Extra-large seeds mean extra-large plants and these grow 3.6–4.5 m (12 to 15 ft) with luminous 36 cm golden yellow flowerheads and with their much thicker stem it requires no support. That should keep the wildlife happy! Flowers July-September. It doesn't matter which way up the seed is placed, it will right itself as soon as it starts growing, Seed Count Approx - 10 avg SOWING - Mainly sown from mid-April to the end of May. It’s best to sow into the garden (or outdoor containers) after the danger of spring frost has passed. Sunflowers dislike having their roots disturbed, so direct sowing instead of transplanting is best. Plant 1 inch deep & 6 to 8 inches apart. They're easy to grow, & you don't soak sunflower seeds before planting them. It doesn't matter which way up the seed is placed, it will right itself as soon as it starts growing.