To prime the canvas to make it accept the watercolour, I use an absorbent ground by Daniel Smith. It creates some texture too that I like. The ground must cure for 24 hours minimum to be effective. Some times I put multiple layers on with a stiff hoghair brush to create texture.
This painting is of ristras, strings of peppers tied together, that we saw near Sedona Arizona. I liked the weird rusted wheel that was hanging with the ristras too. Ive got the first few layers of watercolour applied now and am starting to add the calligraphy brush work that will add details in some areas. Building lots of texture into the piece too by using dry brush and crosshatching with my brushes too. When the watercolour is finished, I will spray clear acrylic varnish over the painting, usually six layers letting each layer dry in between. This will give it a protective coating so it doesnt have to be framed under glass. It also punches out the colours so they are rich and vibrant. Sometimes before the varnish is sprayed on, the colours can looked a bit faded as they are soaked into the absorbent ground, but its always magic to see the colours revive under the acrylic spray.
I will post a finished photo of the painting when its finished.
Note: Daniel Smith absorbent ground can be applied to any surface - glass, canvas, stones, plastic, you name it - and it makes the surface accept watercolours. But every surface has to be sprayed with an acrylic varnish to protect it as the watercolour stays vulnerable to moisture or damage with out it. Ive used the absorbent ground I got from Curry's Art Supplies too which is still nice, but it takes several layers of the ground to make the surface workable.
This is a good alternative for watercolourists who want to use gallery style canvas and not frame their works. I hate working with acrylics so this is a good option for me.
Will see how much longer this crazy snow storm lasts and how many more paintings I can get done while Im stuck here in my studio. Which is not a bad place to be storm stayed!