Same problem with mine, might be too dry? Come to think of it, the nice ones I've seen have not been in full sun. Maybe ours need more water for being in full sun? Good luck.

That may be true---however I was under the impression the less sun they received the more green they turned. It seems like a no win situation.Thanks for the reply.

Did you perhaps buy Crimson Pygmy barberry? It supposedly only gets 2 ft X 3 ft & in my experience is a very slow grower, showing very little growth for the first 3 years, then a nice spurt, but still pretty small shrubs. My 4 Pygmy barberries, bought as very small shrubs, have not reached 2 X 3 in five year in my zone 5 garden.

Rose Glow Barberry does easily grow 4-6 ft tall and wide here, although people do have a tendancy to trim them down into smaller meatballs.

I am not sure exactly what type of barberry they are. We are in a new subdivision and they were all planted by the builder at all of the homes. Thanks alot for the response. I may relocate them to see if they can find a HAPPY PLACE.

This is not an answer to your question, but I hope a tactful observation. Barberry is on the "invasive" list in MA, and I bet in some other states. Maybe this an opportunity to replace this with another plant, perhaps a native, or at least with something that doesn't compete so effectively with our native flora.

My 'Crimson Pygmies' are 3' tall x 5' wide after ten years. I wish they were as small as advertised. I think pruning them back several times made them grow more.....