Hi Ya, You say your blueberries are not producing fruit. I wonder how big the pots are they are in? it is said they need a minimum 18" pot and bigger if possible, mine are 27 litre pots. Also do you add a layer of fresh compost each season and a handful of acid granules ie: Azalea feed, I was also advised to feed once a month in water a liquid feed. I keep mine, as they are acid lovers, in pots in a gravel tray and always plenty of water as they love moisture. I would be tempted to pot them on now while dormant into a bigger pot with fresh acid compost and see how you go. You probably know this already so apologies for teaching you suck eggs but my mentor gave me this advice and he had been growing them for several years. He also said about having different varieties to help with pollination as they benefit from that as well so maybe try introducing a few different ones. Good luck with the project and I hope this will be of some help to some one.