The blue area is like an oasis on the bright side of the planet (The planet is tidally locked, so one side is always day and the other always night, making one side very hot and the other very cold respectively. This also means that it is technically always sunset at this spot). The plants are pitch black because the star is a red dwarf, which are quite dim, and, as such, the plants try to absorb as much light as they can, making them dark. This is also somewhat based on the JWST image on google (As well as many depictions), thus the clouds and desert.
credit to -teamocean2-
