In message , Neale
writes
I want a (moderately) vigorous climber for a north facing, painted brick
wall. The bricks and mortar are very hard, and a lot of things have
struggled to self-cling. Any suggestions of what would suit would be
gratefully received.

Hydrangea petiolaris looks good and likes these conditions if you are
reasonably patient. It takes a few years to get going though.

Regards,
--
Martin Brown