Flower beds carried first of tulips in botanical garden (9)
I believe the answer is:
'botanical garden' is the definition.
'flower beds carried first of tulips in' is the wordplay.
'flower beds' becomes 'arum' (I can't explain this - if you can you should believe this answer much more).
'carried' becomes 'bore' (I've seen this in another clue).
'first of tulips' becomes 't' (ast letter of 'tulips').
'in' is an insertion indicator.
'arum' going around 'boret' is 'ARBORETUM'.
Can you help me to learn more?
(Other definitions for arboretum that I've seen before include "Garden where trees and shrubs are cultivated", "Where planes may be", "Place for cultivation of trees", "Place for cultivation of 19s", "Collection of elders, say".)