Recently in one of my classes, Jenny Wong did a demonstration of how she uses gouache in her landscapes. Jenny is a very talented artist and her landscapes are beautiful. Check out her website at http://www.jennywongart.com/.
When I paint in watercolors I hardly use gouache at all. Sometimes I use a little bit to depict snow or mix with another color to show an area that needs to be more opaque. I mostly paint with transparent watercolors and I enjoy the build up of transparencies that allow your colors to come alive. Adding the gouache gives a more opaque covering of the paint. I think the colors are bright and clear. It gives a look almost like acrylics or oil painting. It is just a different way of painting.
I enjoyed doing this painting. It gave me a feeling of freedom. Was that because there was no sense of needing to be successful? Or perhaps because it was a simple subject? I really do not know but it sure was fun and I will try it again.