To increase the shadows, I applied a brown oil wash where I wanted them darker.
Inspired by TWS's video "Sand 2.0", I used terrarium sand, grass tufts and coarse turf. The ingredients were glued on, then sealed, done. No painting. I sieved the sand in three grades; first I glued on some larger rocks and sprinkled some of the medium sand around these. When that was dry, I covered the rest of the base in PVA, added some coarse flock here and there, sprinkled on some of the medium grain in a random pattern, added some grass tufts where there was enough room, and then dumped the fine grain all over to cover the rest.
Also on some of the higher ridges, I used the medium and fine sand. As it doesn't really stand out there, my color choices for the spires seem to work out :-)
Finally I glued the burnt flock and a dark green flock into shadow areas, as I imagine there dew to collect and that combined with being covered from the sun, some moss will grow.
Once the glue was dry, I sealed the bases with Paepercuts Scenic Glue Recipe. Finally for additional protection the models got a coat of matt varnish.
Here are the finished spires in their storage box.
