Heuchera grows best in fertile, well-drained soil that contains some lime. Preferably place the plants in partial shade for the most beautiful leaf colors.
Every 3 years it is good to rejuvenate the plants: take them out of the ground, remove the long rhizome and replant the small, separate plants with small roots and a little rhizome. This way you keep the plant compact and with large leaves.
General care tips can be found here