The common sunflower (Helianthus annuus) is very popular all over the world.
https://en.wikipedia.org/wiki/Common_sunflower; https://www.kew.org/plants/sunflower
This year’s Hokuto City Akeno Sunflower Festival was held during July 19 through August 17, 2025. https://hokutosunfes.com/
Common sunflowers, Akeno, Hokuto, Yamanashi, 8/20/2025
Double-flowered sunflowers (Helianthus annuus), Akeno, Hokuto, Yamanashi, 8/20/2025
Sunfinity sunflowers (Helianthus interspecific), Akeno, Hokuto, Yamanashi, 8/20/2025
https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=437613&isprofile=0&pt=1; https://mygardenlife.com/plant-library/sunflower-sunfinity-helianthus-interspecific
Also, please visit the sites of my previous articles: August 24, 2023: https://yamanashietsuo.net/sunflowers-and-apples/, August 19, 2018: https://yamanashietsuo.net/2018/08/, and August 13, 2022: https://etsuo.tokyo/2022/08/.
FYI
Vincent van Gogh Sunflowers: https://www.sompo-museum.org/en/collection/gogh/
Akeno Sunflower Festival 2026: https://jal.japantravel.com/yamanashi/akeno-sunflower-festival-2025/59604