Soil the planet (5)
I believe the answer is:
earth
I believe this is a double definition.
'soil' is the first definition.
(synonyms)
'planet' is the second definition.
(Earth is an example)
'the' is the link.
(Other definitions for earth that I've seen before include "our home" , "Dirty hole" , "Our favourite planet" , "Soil; electrical ground" , "wire" .)