Variety of tape useful to gardeners (4)

I believe the answer is:

peat

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'useful to gardeners' is the definition.
I can't judge whether this definition defines the answer.

'variety of tape' is the wordplay.
'variety of' indicates anagramming the letters.
'tape' is an anagram of 'PEAT'.

Can you help me to learn more?

(Other definitions for peat that I've seen before include "Fuel from boggy land" , "Fuel from bogs" , "Dried turf" , "Partially carbonised vegetable matter used as a fuel when dried" , "Bog material" .)

I've seen this clue in the Evening Standard.

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