The Day of the Triffids is a 1962 British science fiction horror film based on the 1951 novel of the same name by John Wyndham. The film follows a group of survivors struggling to survive in a post-apocalyptic world overrun by carnivorous plants known as Triffids.
From Wikipedia
The Day of the Triffids is a 1951 post-apocalyptic novel by the English science fiction author John Wyndham. After most people in the world are blinded by an apparent meteor shower, an aggressive species of plant starts killing people. Although Wyndham had already published other novels using other pen name combinations drawn from his real name, this was his first novel published as "John Wyndham".