- It ain't gonna grow anymore. I promise.
- How can you be so sure?
- It ate three times already.

6 seconds sound clip from the The Little Shop of Horrors (1960) movie soundboard.

You can hear this line at 00:44:03.875 in the Blu-ray version of the movie.

Quote context

[...]

- Alright, Seymour. Now you tell me if this plant is finished all grown up.

- It's finished all growing up.

- You wouldn't kid your father?

- My father came home?

- Me, idiot!

- It's a finger of speech.

- Now, look... I can't stand anymore that plant. It's growing me out of house and home.

- It ain't gonna grow anymore. I promise.

- How can you be so sure?

- It ate three times already.

- Who... I mean, what did it eat this time?

- Well, about a million Japanese beetles.

- So don't eat no more?

- It's full.

- There's a lady from some kind of a committance outside. I think it's important.

- Excellent.

[...]