My Pathetic Blueberry

So I'm sitting on my patio while the girls play in the sandbox, and I need to share about my pathetic blueberry bush.  I have a blueberry bush that my mom ordered for me about 3 years ago as a very small plant from some catalog - Burpee, maybe, I'm not entirely sure.  At the time we didn't really have a good space worked up to put it in, so I planted it in a large pot - one that came with a fairly substantial tree we planted that year.  Three years later, the blueberry is still in the same pot, but it is rather pathetic and I can't quite figure out why.  The pot is plenty large for it - I haven't taken it out of the pot to check it's roots, but it's still a fairly small plant and I can't imagine it being root-bound in the pot it's in.  Every year I give it a couple inches of compost on the top of it, but I don't fertilize it with much else.  Before I converted to solely organic gardening last year, I'd give it a weak dose of synthetic fertilizer every so often.

We finally have the small (3'x3') raised bed built for it, and as soon as it dries out enough to work the ground up I'm going to be digging in compost, mulch & peat moss in the spot it will go.  However, I'm a wondering if this thing is ever going to really take off and produce fruit.  This year I gave it a hearty 2-3 inches of compost in the top of the pot, and some hollytone since blueberries are acid loving.  At this point we'll wait and see.  Kate absolutely loves blueberries, so it would be really nice if this bush would actually grow and produce fruit!