11a. A trip out of town! (7,5) C?U?T?Y-?A?C? (Thinking Country March?)
15d. Can put up the price for fertiliser (7) N?T?A?? (Thinking Nitrate, but nor sure how that fits in with the first part of the clue?)
23a. Given payment to do the catering (4) ???D (2nd letter is last letter of 15d.