Blueberries Wilting with Browning of Leaves

[JackieChan]

One of my blueberries has started wilting and the leaves going brown, here's a photo

I have more bushes in the same pots, compost, plant feed and water and they are all doing great.

Any ideas?

http://img204.imagevenue.com/img.php..._122_361lo.jpg

[JackieChan]

Just to add, they are grown in pots, erricatious compost and fed with an acidic slow release fertilizer. I water regularly.