Does anyone know anything about gardening?

Looking for ways of getting some sound proofing

Obvious solution is to put in a border and grow some plants.

Looking for ways of getting some sound proofing into our garden (I can hear every word of neighbours conversations two doors down)

I'd argue to stop caring about it, unless there's something complete egregious going on.

sound proofing

Others will know much more about sound @freddo maybe(?), but to me that whole area looks like a bit of an echo chamber and a nightmare for amplifying sound. So another +1 to getting plenty of plants to break up the noise.

I've got a deutzia (I think) which is great for that sort of thing. It's nice and green, can grow big, and has pretty pink flowers in spring.

I'd also get a couple of decent rambling roses from David Austin and put them on trellis at the top of that wood fence.

Lastly I'd consider if there is anything you could do to stop sound bouncing back off the big wall at the end. Maybe a pergola, or screening off the last 1/3 of the garden so there's a sort of top terrace.