A large tree next to small plants (7)
I believe the answer is:
alpines
'plants' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.
'a large tree next to small' is the wordplay.
'large' becomes 'L' (eg in clothes sizes).
'tree' becomes 'pine' (pine tree is a kind of tree).
'next to' says to put letters next to each other.
'small' becomes 's' (abbreviation - e.g. clothes size).
'a'+'l'+'pine'+'s'='ALPINES'
Can you help me to learn more?
(Other definitions for alpines that I've seen before include "Plants that grow in mountain areas" , "Natives of heights" , "Plants in mountains" , "Some plants; spaniel (anag.)" .)