Dimwit misplaced geraniums, having nothing for middle of bed (9)
I believe the answer is:
ignoramus
'dimwit' is the definition.
(I've seen this before)
'misplaced geraniums having nothing for middle of bed' is the wordplay.
I cannot quite understand how this works, but
'nothing' could be 'no' ('no' can be similar in meaning to 'zero') and 'no' is located in the answer.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for ignoramus that I've seen before include "I wouldn't know" , "One who knows nothing" , "Stupid person" , "At the present time" , "One could be blissful it's said" .)