Here is a tip.
Let it grow under the fence into the neighbours yards so that you can let it overun their garden and you can still harvest it over the fence.
Also, when having a beer with him, ask him where it come from cause the birds would love it.
He now thinks that harvesting and bagging the seed heads for me that it will reduce the spread
This has gone on till guilt got the better of me and we will help him remove it, mind you it was well established before he moved in.

Living In a Unit is Worse Than Being Attached to a Ball and Chain.