I got asked this question just last week and it made me think of the time I was an art student and I kept hearing the term gesso. I had no idea what it was and felt to embarrassed to ask because I felt it was something I should know. Several years later I found out that it was a primer and it is used to prime surfaces for painting. I use it often and wouldn’t be without it now so it seems funny that it was such a mystery to me for so many years. This is why this site is so useful for so many, there are no silly questions!
Gesso can be referred to as primer and it is used to prime the surface of canvas or paper for painting. Just like painting and decorating when we prime a surface for the paint, gesso does the same, think of it as an undercoat.
Why Prime Surfaces?
Gesso makes the surface of canvas or paper stiffer and creates a slight texture that paint can sit on top of. Without gesso paint sinks into the weave of a canvas or the fibres of paper, making for duller looking colours.
You can prime all sorts of surfaces other than paper and canvas, you can prime wood, vinyl, metal and more. Gesso makes it possible to paint on objects like wooden boxes or metal tins once the surface is primed.
Types of Gesso
There are all sorts of gesso available now in art shops. I recommend getting an all purpose one that just says ‘gesso primer’ on the label. You can then use the gesso for everything. If you only work in acrylics then go ahead and get an acrylic gesso (seen on right).
You can buy tinted gesso, this is simply gesso that has a pigment in it to colour it. I wouldn’t recommend these tinted primers because you can tint your own gesso simply by adding acrylic paint. Tinted gesso tends to be expensive and you may have to buy several if you don’t know what colour you need.
What does Gesso look like?
It is traditionally white but I now see that you can buy clear and black gesso. It is much like white acrylic paint only thicker and various in consistency depending on the quality – thinner gesso tends to be cheaper. It is plaster and water based (you can make your own, but that is another post!) so it doesn’t smell unpleasant and it is nice to use.
How do I use Gesso?
It is really easy, you simply paint it on evenly and leave it to dry. You can now get spray on gesso for a more even surface if you prefer that method. Spray on gesso is slightly harder to find in some art stores however, you may have to purchase it online. Gesso dries in minutes which is great because it means you get started on your painting very soon after your gesso surface is dry. Do allow the gesso to fully dry out, I leave it for at least an hour just to be sure.