Vase on locker

I had a photo that I took of the bedside locker in France with a cheap old vase picked up in a brocante, and some dahlias from a neighbours garden. The support is ArtSpectrum sanded (and wettable) paper.
Initial block in was with Derwent Carmine for the dahlia, Rembrandts for the background and Carbothello pencils for detail over Schminke soft greys for the porcelain and the locker.

Nearly there at this point. Needs a few missing details on right leg of locker, dahlia must be sharpened etc. I found that the Schminke is so sofe it has taken up all the tooth and when I tried to work further on locker edges and contiguous background the support was not at all receptive and began to get very sulky, losing all tooth and refusing to accept any pastel at all. I tried masking off the affected area and spraying with fixative, but that was not very useful; so I ended up by brushing off all pastel from around the affected area and painting a thin layer of acrylic gesso on the support. This gave me the tooth I needed to finish.