5d Fruit — 25 up? (5) [25d is LASSO] L-M-S presumably LIMES, but why?
13a Something grand (no! no!) into blue green sculpture (7) I have crossing letters which would fit TOPIARY (green sculpture), but don't understand rest of clue!
4d Deny what may be said with very pained expression (7) D---V-W Presume DISAVOW but why?
4a Problem picking up call girl (7) Have crossing letters for DILEMMA but why?
9a Popular fix during the day produces interest (9) I-T---U-S No idea!!!
18d Opening bat not opening, two ways not straight about it (7) --T--W-Y (?GETAWAY ?PATHWAY)
5d is LIMES. It's SEMI-L upwards, i.e. half of L (fifty) = 25.
13a is TOPIARY. PIA(NO) in TORY (blue) to give green sculpture
4d Anagram of SAID = DISA + V (very) + OW (pained expression)