I always try to separate them, and when I take my stuff down to the garbage I always put bottles/cans bags separate beside the garbage rather than in it. I know the older ayi ladies at the compound try to collect up bottles and some specific materials (like cardboard/etc) so rather make it a little easier for them.
That’s a good practice. It had never occurred to me that I should be recycling in China, but there’s a monetary incentive for all the bottles to be collected by someone, so separating them makes sense.