Jacquemontia sandwicensis is a low-growing groundcover which requires little water and is salt tolerant, which makes it ideal for growing on the coast. The little blue or white flowers bloom year round. One of the morning glory family (Convolvulaceae), it’s endemic to Hawaii, where it’s known as Pāʻuohiʻiaka.
Morning glory vines spread through, what I think is sea purslane, at Pu’uhonua o Hōnaunau National Historical Park.
For more information about Pu’uhonua o Hōnaunau National Historical Park, visit https://www.nps.gov/puho/index.htm.