I poked holes in the top of my pots, then ran long zip ties through them. I have a pole with a hook on it, too, so I use that to hook the zip tie.
I used to use rope instead of the zip ties, but then one of them broke while I was pulling it out due to rot. That made a mess, so I switched to zip ties.
I have a ton of hanging baskets just sitting around, though, so I wish I'd thought of that one myself!
@cas, I love how your coneflower looks next to the pond!