I've had bad luck with the lighter Heucheras in sun. The only one to do well for me is "Peach Flambe."

Bummer :( I planted two of them a couple of weeks ago..in sun.

I have two Caramel Heuchera in full sun. Both are doing fine in Zone 5 Michigan in clay soil which is moisture retentive. Three Peach Flambe are on the other side of the bench, also around a Mops Mugo Pine (max size listed as 2 ft by 2 ft). These are also in full sun and do very well, but have not grown as fast has Caramel for me.

I just posted this picture in another thread yesterday, so I apologize, but this is the only picture I have of Caramel that shows its siting. Although the camera sort of squashes things closer together, there is nothing except the small 18 inch tall heucheras in the middle to block the sun. They are on the outside edge of the circular part of a peninsula bed that juts out more than 10 ft from the dwarf Hawthorn tree, well outside its shade line & in the most open part of the yard. Perhaps the clay soil is the thing that holds enough water to keep them growing well in lots of sun, since zone 7 Long Island sun shouldn't be all that more intense than mine.
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