That amount of sunlight should be just fine. I have 6 blueberry bushes, all different cultivars and all are thriving, despite the fact that my soil is a terrible clay and I have no idea what the pH level is. People always advise you to make sure to give your blueberries plenty of acidic fertilizer or they won't do well, but unless I've gotten extremely lucky, I'd say that recommendation is a little overblown. They also say you need well drained soil (what doesn't?) but like I said, I have clay other than the topsoil I planted them in. I think they're tougher than most people give them credit for.