Crossword Genius

It's a heap of use to gardeners (7)

Ross

I believe the answer is:

compost

I'm a little stuck... Click here to teach me more about this clue!

'a heap of use to gardeners' is the definition.
I can't tell whether this defines the answer.

'it's' is the wordplay.
I cannot quite see how this works, but
'it' could be 't' (abbreviation. e.g. in 'tis) and 't' is found in the answer.
The remaining letters 'compos' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?

(Other definitions for compost that I've seen before include "Decaying vegetation as fertilizer" , "Fertilizer for plants" , "Decayed organic matter" , "Fertiliser (from heap or bin)" , "material that promotes growth" .)

I've seen this clue in The Globe and Mail.
Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.