The flowers are 5 -- 10 cm diameter .
The flowers have 6 to 12 ( most often 9 ) bright yellow petal - like sepals ; the true petals are small , hidden near the stamens .
The flowers are 5 -- 10 cm diameter , and have 6 to 12 ( most often 9 ) bright yellow petal - like sepals ; the true petals are small , hidden near the stamens .