Of course, hops don't restrict themselves to hop gardens, and wild - or perhaps feral - hops abound in many hedgerows (and now growing vigorously).
Many hedgerow hops are male, unlike the ones with the cones in the hop gardens which are all female, and historically these self-sown plants would have been removed by local growers since unseeded hops could command a premium.
However, there can be serendipity here too, such as the new variety of wild hop discovered in Sussex and now used by Harvey's for one of its brews: Wild Hop.