I had some thoughts on Triffids a while back and noted them down here: Thoughts on The Day of the Triffids by John Wyndham
Basically, I agree that it's a very powerful and skillfully-written book. To my mind only The Midwich Cuckoos betters it. My mental image is of it being set slightly before now, rather than just after WW2, which goes to show how well it has aged, I think. However, I found the women quite weakly-portrayed, and felt that they had that childish, act-on-a-whim quality that ages a lot of novels for me. That said, Wyndham is no worse than many other (later) writers for this, and perhaps slightly better than usual.