Macrophyllas' leaves are more sensitive to the sun than paniculatas' leaves are. Here in the Dallas area (Dallas and Atlanta are approx in the same latitude), Macrophyllas' leaves suffer from sunscorch during the height of the summer if allowed to get sun past 11am-12pm (that is, the leaves turn all yellow, including the leaf veins). Glyn Church recommends these for sunnier places but these too require protection from the afternoon summer sun: Altona, Ayesha, Blue Wave, Lilacina. In the northern half of the country, macrophyllas can withstand more sun than they do here.

Even in the rather northerly reaches of the PNW with our not very intense summer sun, H. macrophylla planted in full sun suffers - daily wilting, leaf scorch, bleached out foliage color and more stunted growth than those that receive at least some afternoon shade relief.

I'm not sure I'd chance it :-)

Good question. When ES first came out I heard folks were putting them out in full sun with no problem. Not for me, I moved mine into full sun and eventually had to spend a summer with beach umbrellas in my front yard to shade them. Can't believe I never took a pic. One passerby thot it was "art." lol. Moved them to shadier locales the next year.

Good luck.