The Haves and the Have Nots

We is spending a lot of time on the back lawn at the moment. 

You see, there is a plum/plumb tree and on this plumb tree is little green plum/plumbs.  And these little green plumbs make the best chewy in the world even though they is hard and bitter.  We get to pick up all the plumbs that the birds don't get, on account of they was very late in putting the bird netting over, and in any case the birds is so clever they can get underneath.

This is me Harry - I like the little green plumbs better than Georges does, but as soon as I get one he wants it whether he likes them or not.

Next year apparently they is going to prune it back hard so that it's easier to net, and then they might get some plumbs for themselves.

This is me George - why is English so hard to understand?  There is plums and there is plumbs and they do both sound the same, but according to HER they is quite different, and you can only tell which is which depending on the context - whatever that is.