  We construct a set of model spectra specifically designed to match the
colours of the BOSS CMASS galaxies and to be used with photometric redshift
template fitting techniques. As a basis we use a set of spectral energy
distributions (SEDs) of single and composite stellar population models. These
models cannot describe well the whole colour range populated by the CMASS
galaxies at all redshifts, wherefore we modify them by multiplying the SEDs
with $\lambda^{-\beta}$ for $\lambda>\lambda_i$ for different values of
$\lambda_i$ and $\beta$. When fitting these SEDs to the colours of the CMASS
sample, with a burst and dust components in superposition, we can recreate the
location in colour spaces inhabited by the CMASS galaxies. From the best
fitting models we select a small subset in a two-dimensional plane, whereto the
galaxies were mapped by a self-organizing map. These models are used for the
estimation of photometric redshifts with a Bayesian template fitting code. The
photometric redshifts with the novel templates have a very small outlier rate
of $0.22\,\%$, a low bias $\langle\Delta z/(1+z)\rangle=2.0\cdot10^{-3}$, and
scatter of $\sigma_{68}=0.026$ in the restframe. Using our models, the galaxy
colours are reproduced to a better extent with the photometric redshifts of
this work than with photometric redshifts of SDSS.
