Fresh day lily contains slightly toxic colchicine, which is easily decomposed when heated and easily dissolved in cold water. Blanch the day lily with boiling water first, then soak it in cold water for a while, then take it out, drain it and dry it in the sun. Choose to dry on a sunny day, preferably on a concrete floor, and don't use some bamboo frames with strong water absorption.
Usually, the buds harvested by fresh day lily should be steamed together with the harvest to prevent the collected buds from continuing to open and affecting the quality. The method of steaming fresh day lily is: spread the collected flower buds in a boiling steamer, cover the steamer and steam for a few minutes until the color of the flower buds changes from yellow to light yellow. When the handle is squeezed by hand, the flower buds will droop, indicating that the steaming is done.