It all depends if you are talking about the decorative sunflower, or the flower that bears the edible seeds. The decorative flower can be about 25 cm in diameter, and the sunflower with the edible seeds almost twice that.
Not necessarily. While a smaller than average head will definitely have smaller seeds, a larger than average head will simply have more seeds of the typical size. There is an upper limit on how large sunflower seeds can be (the limit depends on the breed of sunflower).
Depending on the size of the sunflower - 34, 55 or 89
The average size of a sunflower is 2.5 meters (about 8 feet).
a sunflower is about 8-12 feet tallup to 8 feet tall
sunflower
Sunflower starfish can grow quite large, reaching a diameter of up to 3 feet (about 90 centimeters) or more. They typically have between 15 to 25 arms, which contribute to their expansive size. These starfish are known for their distinctive appearance and can weigh over 5 pounds (around 2.3 kilograms).
By eating sunflower seeds
41x51 cm (16x20 in).
sunflower, tree, cactus,
A cardinal can help increase the size of the sunflower population in its ecosystem by feeding on sunflower seeds and unintentionally spreading them around through its droppings. This helps disperse the seeds to new locations where they can germinate and grow, contributing to the overall population of sunflowers in the ecosystem.
Helianthemum.
The sunflower is regarded as the king of the flower because of the large flower that it has.