put down roots
Settle somewhere, become established, as in We've put down roots here and don't want to move away. This metaphoric expression, first recorded in 1921, likens the rooting of a plant to human settlement.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.