The heavy rain over the winter may have caused a few problems too, leaching nutrition out of the soil. I've had several Fatsias, in different gardens, and they do get a bit bleached if they get too much sun so they need a better, more moisture retentive soil if they're in that aspect, but they don't like sitting in wet ground either. The wind does give them a bit of a hiding as well. I planted one in the front border in this new garden last year but it's too exposed there, so I'll find a better location for it. They're great plants if you like a jungly look too.