Sunflower seed flourishes well under well-drained moist, limey soil. It prefers good sunlight. Domesticated varieties bear single large flower-head (Pseudanthium) at the top. Unlike its domestic cultivar type, wild sunflower plant exhibits multiple branches with each branch carrying its own individual flower-head. The sunflower head consists of two types of flowers. While its perimeter consists of sterile, large, yellow petals (ray flowers), the central disk is made
up of numerous tiny fertile flowers arranged in concentric whorls, which subsequently convert into achenes (edible seeds).
Sunflower seeds are about 6 mm to 10 mm in length and feature conical shape with smooth surface. Their black outer coat (hull) encloses single, gray-white edible-kernel inside. Each sunflower head may hold several hundreds of edible oil seeds.