David,
When you say "Geraniums", what are you meaning? Are you meaning the old geraniums that are in gardens everywhere (i.e zonal pelargoniums), or are you meaning the hardy geranium species? I think of the old commonly called geraniums (i.e Zonal Pelargoniums) as being grown by cuttings, whereas the hardy geraniums are grown by division/runners etc. Thought I would check. If you're meaning the zonals, then most of them will grow from cuttings as far as I know. Some of the hardy geranium species I find can resent disturbance a bit and sulk after division, at least in my climate.