put roots down
To establish something, someone, or oneself as a permanent resident or establishment in a certain place. I'd been living in this country for a few years, but it wasn't until I had kids that I felt like I had really put roots down here. The company is keen to put roots down in the region, which they see as a huge untapped market.
put roots down (some place)
to settle down somewhere; to make a place one's permanent home. I'm not ready to put roots down anywhere yet. I'm ready to put down roots someplace. I want to settle down. I want to put roots down and buy a house.