Since I'm on the West coast, I can't really give advice.
However, if there is a problem, it's probably due to the humidity/moisture during your warm months. Over here, it is quite dry in the summer...unless you go north into the foggy redwood zone - in which case, the temps are considerably lower. I can't say with any certainty, but you might have success by planting them in raised mounds or on a site with good drainage (to help during the wet warm months).

Josh

Thanks Josh I will try a I will try a real well drained spot and cross my fingers.
Peter