Laurel spreads in eastern edge of allotment fast (7)
I believe the answer is:
instant
'fast' is the definition.
(similar in meaning)
'laurel spreads in eastern edge of allotment' is the wordplay.
I cannot quite see how this works, but
'laurel' could be 'stan' (comedian Stan Laurel is an example) and 'stan' is found in the answer.
'in' is found in the answer.
A single letter 't' remains which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for instant that I've seen before include "A second - coffee, maybe" , "The blink of an eye" , "Split second" , "No need to cook" , "Trice" .)