Greenhouse on the couch, niggas seeing me toast
from Rick Ross – MMG Untouchable Lyrics on Rap Genius
Meaning
Ross smoking so much jane that he hotboxed the shit outta himself, similar to a greenhouse that keeps all the moisture and air inside to refresh and nurture plants

He could also be referring to club Greenhouse in NYC. He’s standing on the couches and popping bottles. That’d be the reason the aforementioned “niggas” are able to see him toast.
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