Helianthus annuus F1. Tidy, semi-dwarf sunflower plants that are fast-growing and great for cut flowers. The first flower appears only 60 days from planting. These little plants only grow to 70cm (28″) tall, with amazing geometrical flower centres that demonstrate “Fermat’s Spiral.” That is the pattern that reveals the most compact method of packing items into a small area. Zebulon Sunflower Seeds produce sunny flowers that are a uniform 15cm (6″) in diameter. Zebulon sunflower seeds are a hybrid bred in Europe for the florist industry. Each strong stem bears a single, uniform flower that work beautifully as cut flowers in the summer.