Houttuynia cordata Chamaeleon is my next offering. I know some will be horrified as it is supposed to spread a lot, but mine has the concrete wall of the scree on one side, a brick wall on the other and paving in front. If it pops up between the paving it gets pulled out, but that doesn’t happen very often. It makes a nice splash of colour and when the leaves are crushed I can smell oranges!