Growing medium vegetable at end of allotment (4)
I believe the answer is:
peat
'growing medium' is the definition.
The definition and answer can be both substances as well as being singular nouns.
Maybe you can see an association between them that I don't see?
'vegetable at end of allotment' is the wordplay.
'vegetable' becomes 'pea' (pea is a kind of vegetable).
'at end of' says to take the final letters.
The last letter of 'allotment' is 't'.
'pea'+'t'='PEAT'
Can you help me to learn more?
(Other definitions for peat that I've seen before include "Vegetable matter in bogs, like turf" , "Fuel from boggy land" , "Form of fuel" , "Saturated and compressed vegetable matter, used as fuel when dried out" , "Partially carbonised vegetable matter used as a fuel when dried" .)