The poysean is a hybrid of Thai origin; a cross between the crown-of-thorns (Euphorbia milii Desmoulins) and the white crown of thorns (Euphorbia lophogona Lamarck). Although in Thailand, the name refers to the parent plants and the hybrids. Both parent species are native to Madagascar.

The flower is not a flower; it is an inflorescence properly called a cyathium. It consists of one greatly reduced pistillate (female) flower surrounded by three greatly reduced staminate (male) flowers. Each of the staminate flowers consists of a single stamen.

Surrounding the flowers are glands, in the photographed plant, the glands are yellow. Subtending the flowers and glands are two brightly colored bracts or cyathophylls. The inflorescences of the poysean are borne in cymes.

The Thai have been hybridizing and selecting Euphorbia x lomi for about 30 years. The results of their work are a spectacular collection of poyseans--well over two thousand hybrids. Since growers outside of Thailand have also been hybridizing E. milii and E. lophogona, the Thai hybrids are referred to as Euphorbia x lomi Poysean Group.

According to various sources, the name poysean comes from two Chinese words meaning 'eight saints'; holy men who sacrificed all they had to bring righteousness to the world. The plant is considered lucky and many people in Thailand own at least one.

The University of Florida Cooperative Extension Service of Miami-Dade County has produced an informative brochure on crown-of-thorns and the many hybrids. To learn more about the plants, including growing tips, click on the link:

http://miami-dade.ifas.ufl.edu/programs/commorn/publications/crown-of-thorns-homeowner.PDF