General description and special characteristics – The sunflower is an upright annual plant that varies in height from 1-4 m. The sunflower is a North American species. Evidence shows that its cultivation by Native Americans, in what is now the Western United States and central highlands of Mexico, dates back to 900 B.C. Domestication encouraged unbranched plants bearing single large flowering heads that produce larger seeds.
- Black Seed (พันธุ์ท้องถิ่นสำหรับสกัดน้ำมันเมล็ดสีดำ): Local Northern Thai variety with kernels black in color. Can grow between 2-3 m in height.
- Chiang Dao (พันธุ์ท้องถิ่นสำหรับกินเมล็ด): A local variety that averages in 2.5 m in height. The flowers are around 15 cm across and petals are yellow in color. The seeds have a striped pattern and the kernel is quite tasty.