Hi Kathy! I contacted M.Graham for you and here is what they said:

"The honey in our formula keeps our watercolor moist on the palette and in the tube.  It will dry normally when used in a wash application.  For those who want to do thicker layers, we make a fine art gouache.  The colors are matched to the transparent watercolors for mixed media work.  Since our gouache is for finished fine art, we did not add the chalks and whiteners found in "designers" products, leaving the choice to add white to the artist.  Any painters who have issues with our color are more than welcome to contact us at colormaker@mgraham.com "