From Wikipedia:

Delonix regia is endemic to the Madagascar's dry deciduous forests, but has been introduced into tropical and sub-tropical regions worldwide. In the wild it is endangered, but it is widely cultivated elsewhere and is regarded as naturalised in many of the locations where it is grown:
North America[edit]
In the continental United States, it grows in South Florida, Central Florida,[3] and in the Rio Grande Valley of South Texas.Caribbean and Central America[edit]
In the Caribbean it is featured in many Dominican and Puerto Rican paintings. It can also be found in Belize, The Bahamas, Cuba, Haiti, Nicaragua, U.S. Virgin Islands, Cayman Islands, Jamaica and Curaçao. It is the national flower of St. Kitts and Nevis. It can also be found in Bermuda, Hawaii and Mexico, especially in the Yucatan peninsula. The town of Peñuelas, Puerto Rico, located about 12 miles or 19 kilometers west of Ponce, is nicknamed "El Valle de los Flamboyanes" ("The Valley of the Poinciana Trees"), as many flamboyant trees are found along the surrounding Río Guayanes, Río Macana, and Río Tallaboa rivers.South America[edit]
It grows in Paraguay, Peru and throughout the whole of Brazil.[4][5]Europe and the Middle East[edit]
Delonix regia is planted in Mediterranean parts of Europe, the Middle east and North Africa, including the southern coast of Spain, the Valencian coast, the Canary Islands, Lebanon, Egypt, Israel and Jordan.South Asia[edit]
The tree is planted in India, where it is referred to as the May-flower tree, Gulmohar or Gul Mohr[6] in West Bengal, Odisha, Bangalore and Sri Lanka. It is also grown in Karachi, Pakistan. In Mauritius and La Réunion it announces the coming of the new year.Southeast Asia[edit]
In Myanmar, where it is called Sein-pann-ni, the time of flowering is March in the south and early to late April in the north. It is planted in gardens and as a roadside tree. In Myanmar, this tree is a sign of Thingyan Festival (Apr 13 - 16/17). In the Philippines, its flowering signals the imminent arrival of the monsoon rains. It also grows in Thailand and Indonesia and is the official tree in Vietnam. In that country, this tree is called "Phượng vỹ", or phoenix's tail, and is a popular urban tree in much of Vietnam. Its flowering season is May–July, which coincides with the end of the school year in Vietnam. Because of this timing, the flower of poinciana is sometimes called the "pupil's flower". The tree is also commonly found on school grounds in Vietnam, however after several trees fell down, with one student killed, schools started cutting down or severely pruning the trees.[7] Hải Phòng city is nicknamed "Thành phố hoa phượng đỏ" ("City of red poinciana").East Asia[edit]
It grows in Southern China and Hong Kong. It is the official tree in Tainan, Taiwan; Xiamen, Fujian Province, People's Republic of China (PRC); and Shantou, Canton Province, (PRC). National Cheng Kung University, a university located in Tainan, put royal poinciana on its emblem.Australia[edit]
It is very widely grown in the Northern Australia, the southern extremes previously limited to South East Queensland where it is a popular street tree in the suburbs of Brisbane. It now grows and blooms successfully in Sydney and other parts of New South Wales. Micronesia[edit]
It grows in Guam, and is the official tree of the Commonwealth of the Northern Mariana Islands.
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