  We extend the slow blow up solutions of Krieger, Schlag, and Tataru to
semilinear wave equations on a curved background. In particular, for a class of
manifolds $(M,g)$ we show the existence of a family of blow-up solutions with
finite energy norm to the equation {equation} \partial_t^2 u - \Delta_g u =
|u|^4 u, \notag {equation} with a continuous rate of blow up. In contrast to
the case where $g$ is the Minkowski metric, the argument used to produce these
solutions can only obtain blow up rates that are bounded above.
