So that would make it rubbish disposal. (I'm just trying to get the wording right.)Or perhaps she could offer a large sum to take him off her hands? And a Christmas cake? He's very useful in the garden, I hear.
May I suggest she try fly tipping. Much cheaper, well, free. And she could keep the cake for herself.
I'm sure as a useful gardener, he'd be happy to dig his own way out of the ditch.