Day of the triffids trilogy

"What if a meteor shower left most of the world blind--and humanity at the mercy of mysterious carnivorous plants? Bill Masen undergoes eye surgery and awakes the next morning in his hospital bed to find civilization collapsing. Wandering the city, he soon realizes that surviving in this new world requires evading strangers and the seven-foot-tall plants known as triffids--plants that can walk and can kill a man with one quick lash of their poisonous...

Genetic mutation has devastated the world and a bleak, primitive society has emerged from its ruins ; a society which punishes any deviation from rigid norms.Ten-year-old David is having strange dreams about a mysterious city. But in his ultra-religious village of Waknut, all abnormality is abhorred, and he soon realizes that differences can be very dangerous indeed.