A thorough spraying with soapy water--organic soap, preferred--followed by weekly washing of the foliage with plain water has worked the best for me.

Red spider love hot, dry, sunny conditions. As above, a spray over the leaves when it's warm....particularly the underside of the leaves will help. Not tried it with soapy water but you can get sprays from the garden centre.

I cut down all my rose branches. The spraying has got to be VERY VERY VERY thorough cos they like to dwell on the undersides of the leaves - meaning you have to invert your pot of plant to spray at the undersides?!

I gave up with the spraying in the end and pruned all branches in the end. Got defeated by the spider mite army :/

http://www.norfolklights.com/spray-safe-canadian-xpress-p-2142.html

Yes, once they really take hold, they are almost impossible to get rid of. Another gardening situation where an ounce of prevention is worth a pound of cure.