You can use watercolor on normal canvas

canvas

Watercolor can also be painted on canvas. On this medium, however, the watercolor paint has partly different properties than on normal watercolor paper. The surface of the canvas is extremely weakly absorbent, which leads to repulsion reactions of the aqueous paint. However, the surface of the canvas can be pre-treated with special primers for watercolor and thus the repellent properties can be softened a little. If you don't have a primer, it is sometimes enough to wipe the canvas with alcohol and degrease it with it.

You should always keep in mind that the paint does not penetrate much into the substrate. This means that the color already appears much stronger with the first application and dries in the same color strength. The paint should rather be applied thickly, because wet on wet as a technique is only suitable for certain effects, because the paint on canvas is even less controllable than on paper.

You should also keep in mind that painting in layers (glazes) is not very successful, as the lower layers can easily be loosened. However, you can use a medium that makes the paint waterproof after it dries. So you are also able to apply glazes. Alternatively, you can also work with waterproof inks.

The final fixation with a fixing spray is important here. Since the picture is not protected by a glass frame, the paint could dissolve very quickly in a damp place (e.g. bathroom) and ruin the picture.

In my opinion, watercolor painting on canvas is well suited for abstract, non-representational painting, where color gradients are intended to appear uncontrolled. You can experiment a lot here and play with the colors.

An alternative is a photo on canvas. If you don't want to paint yourself, you can quickly turn a successful photo into a work of art.