Politician from D?il ?ireann is sowing the seeds of something big perhaps
I believe the answer is:
greenhouse
'?ireann is sowing the seeds of something big perhaps' is the definition.
I can't judge whether this defines the answer.
'politician from d?il' is the wordplay.
'politician' becomes 'green' (eg member of the Green Party).
'from' says to put letters next to each other.
'd?il' becomes 'house' (I can't explain this - if you can you should give a lot more credence to this answer).
'green'+'house'='GREENHOUSE'
Can you help me to learn more?
(Other definitions for greenhouse that I've seen before include "see-through construction" , "A place for growing" , "Horticulturalists' glass building" , "somewhere hot" , "Glass building for rearing plants" .)