Posted: 01/10/2016 at 18:04
Early flowering plants are useful for bumble bees, they're out and about early. There are plenty of summer flowers without making extra effort. I have a very early flowering pulmonaria, P. rubra I think (though it could be a hybrid, I never get seedlings ) crocus, snowdrops and Nonea lutea which has germinated over the last few weeks and will flower February/March in normal years but was flowering on NYD this year. And some water when it's dry
Can't assess the size of your fly but if it's big have a look at Volucella zonaria, a hoverfly.