I have read the book a number of times, the 70's TV version (it was actually 80's but whatever) is very faithful to the book, this one wasn't, there were elements of similarity.
To answer some of the questions and 'inaccuracies'.
The Triffids were farmed for their Oil, they originally came from the Soviet Union but there was some doubt where they really came from, the suggestion was that they came on a comet. However there is no relation to the meteor storm that blinds people.
The meteor storm was over 24 hours, it did not instantly blind people it took a day or so for it to develop which is why it effected so many people, there didn't seem a danger in looking so most people had the chance to.
The point of the triffids is this, in the book they are not ultra effective killing machines, just slow moving plants with a sting. It is however the combination of millions of blind people and carnivorous plants which is the problem. While there were people to tend them they were easy to handle, but once let loose they were able to pick off the blind.
As for Land Rovers and Blind Watchmen, yes rubbish but not in the book.