  A search for heavy resonances decaying to a $W$ or $Z$ boson and a Higgs
boson in the $q\bar{q}^{(\prime)}b\bar{b}$ final state is described. The search
uses 36.1 fb$^{-1}$ of proton-proton collision data at $\sqrt{s} =$ 13 TeV
collected by the ATLAS detector at the CERN Large Hadron Collider in 2015 and
2016. The data are in agreement with the Standard Model expectations, with the
largest excess found at a resonance mass of 3.0 TeV with a local (global)
significance of 3.3 (2.1) $\sigma$. The results are presented in terms of
constraints on a simplified model with a heavy vector triplet. Upper limits are
set on the production cross-section times branching ratio for resonances
decaying to a $W$ ($Z$) boson and a Higgs boson, itself decaying to $b\bar{b}$,
in the mass range between 1.1 and 3.8 TeV; the limits range between 83 and 1.6
fb (77 and 1.1 fb) at 95% confidence level.
