The Heuchera americana ‘Marvelous Marble’ is easy to care for. Avoid sandy, poor soil and plant in cool and moist soil. Do not place in full sun, preferably the Heuchera in a spot in semi-shade. Heucheras root quite shallowly and so should be planted a little deeper than the crown. Every 3 years rejuvenate the plants, pull out and remove the long rhizome, replant the small separate plants with small roots and a little rhizome.
General care tips can be found here