The Ground

A ground is a stable, absorbent surface to which the paint can permanently adhere. All grounds are composed of gypsum (chalk) and adhesive. A good ground must have durability and a resistance to cracking. The permanence of the finished artwork depends on the structural integrity of the support as well as the ground, both of which bear the same relationship to a painting as that of a foundation to the house built on it. No one would buy a house without having the foundation inspected, yet most artwork is collected solely on surface appearance. Many painters will take great pains to select the highest-quality paints and media to create the best possible surface appearance, yet are incredibly careless in the selection of a proper ground or support.

Many artists assume, for example, that acrylic gesso can be applied to anything to make it safe to paint on. Acrylic gesso, however, should not be applied to tempered fiberboard, because the fiberboard is oil-impregnated and prevents proper bonding of the ground, leading the ground to detach itself as the board ages. Just as much care needs to be taken for what is below the surface as for what is applied on top of it.

In the past, grounds were tinted with lampblack, umber, or green earth to hide the yellowing effect of the linseed oil as it aged. The Holbein Company produces several tinted foundation whites for those who wish to duplicate the look of older painting styles.