The hedge needs a haircut.

As far as correct English is concerned this sentence ‘The hedge needs a haircut.’ although grammatically correct, does not make sense. Hedges grow leaves and twigs rather than hair, yet when I said it to my husband on Sunday morning he understood and replied ‘O.K. I’ll do it tomorrow.’, and a few minutes ago he came in and announced, ’I’ve done the hedge", and the fact is, even if he had said ‘I’ve given the hedge a haircut’, we would both have understood exactly what he meant.