  A graph manifold rational homology $3$-sphere $W$ with a left-orderable
fundamental group admits a co-oriented taut foliation, though it is unknown
whether it admits a smooth co-oriented taut foliation. In this paper we extend
the gluing theorem of arXiv:1401.7726 to graph manifold rational homology solid
tori and use this to show that there are smooth foliations on the pieces of $W$
which come close to matching up on its JSJ tori. This is applied to prove that
a graph manifold with left-orderable fundamental group is not an L-space.
