This alis coat was applied over the brown coat of plaster. This is a variation from painting the alis after doing three coats of plaster (scratch, brown, and finish). After a bit of tweaking, the results were beautiful.
In an effort to save labour costs for the owners, we experimented with time saving measures when applying the plaster to the straw bale walls. The first coat on the bales with a sprayed clay slip, and the second coat was a thick brown coat that was troweled and then hard troweled to shape and smooth the walls.
The alis coat was to be applied directly onto the brown coat of plaster, but we found that darker bits of horse manure were showing through and discolouring the alis. The brown coat also changed the colour of the alis slightly, adding a yellow tinge.
To solve this problem, we tested using wheat paste (flour and water) under the alis coat, with excellent results. So we used a paint roller to apply the wheat paste onto the walls, which is a relatively quick and easy process, then brushed on two coats of alis. The alis no longer showed any discolouration, and we were able to achieve the deep sunshine yellow colour that the owners wanted.