Bit of gardening: raking earth, cutting grass to be collected again (10)

'collected again' is the definition.
('gathered' can be a synonym for 'collected' so perhaps 'regathered' is OK for 'collected again')

'bit of gardening raking earth cutting grass' is the wordplay.
'bit of' indicates taking the first letters.
'raking' indicates an anagram (letters get raked around).
'cutting' indicates putting letters inside (some letters cut their way into a word).
'grass' becomes 'reed' (type of grass plant).
The initial letter of 'gardening' is 'g'.
'earth' anagrammed gives 'ather'.
'g'+'ather'='gather'
'gather' placed into 'reed' is 'REGATHERED'.

'to be' is the link.