The New Guineas do not get the mildew. I thought vinca was for full sun. I have always grown them in full sun and the inpatients in the shade. Other shade annuals that do not get downy mildew are begonia, cyclamen, fuchsia, perilla, torenia and viola/pansies, besides the Lobelia and caladiums which were already mentioned. So there is a lot out there and besides I think the New Guineas are even prettier.
