Well, considering that pattern is just a jpg the only thing you can do is either modify the pattern file itself or overlay something on top of it that would change the hue a bit. For the latter you can just use another background (solid colour of your choice) with transparency on top of this one.
Thank you very much for the reply.
Actually there are 45 patterns and I am not sure which one to use. Plus I am not sure about the color either. So modifying the pattern is not a viable option.
I was thinking about a css filter to modify the Hue but I am not sure if there is such a filter.