At the risk of winning a pedantry medal, isn't the landing speed the speed at touchdown? In which case the answer should be "as slow as possible".
Approach at (say) 60 knots, check, flare, and KEEP PULLING BACK keeping the mains j-u-s-t above the runway (it can take quite a pull a 172 with forward CG to acheive this). Eventually, despite your best efforts to hold it off, the bird will land at the slowest possible speed.
That's how to do it, but to witness the number of 3-point tri-gear arrivals at most GA fields you'd never know it.
SSD