Forget the musical re-make made in the 1980s. It couldn't hold a candle to the original.
"Original" is what this is, too. and nowadays, it's great to have it on DVD in which the audio is clear and the picture pretty sharp.
I have always particularly enjoyed the many humorous lines delivered by Mel Welles, who plays the flower shop owner. He is the real comedian of the cast, although the plant does quite well as do the two leads played by Jonathan Haze and Jackie Joseph. The latter two are a little more subtle in their comedy.
All the characters in here are totally whacked, from Haze's hypochondriac mother to Dick Miller's flower-eating character to the Jewish mother who always has a dead relative to moan about and to the dentist and his patient. The latter, of course, is Jack Nicholson, making his movie debut and looking about 16 years old.
In the end, though, what one remembers most is the plant demanding, over and over, to "Feeeeeed me!!"
For that, the plant and the film never fail to make me laugh.