In message , Mike Lyle
writes
Nick Maclaren wrote:
[...]
sometimes the common
"gardening" name is just plain wrong.

[...]
I can't think of examples of the third, but I am sure that there
are
plenty.

I can't stop my mother calling pelargoniums "geraniums", and a
village school-teacher once contradicted me when I correctly called a
geranium a "geranium". Both are better gardeners than I. And I refuse
to stop calling tropaeolums "nasturtiums". There's "ilex", too. Must
be hundreds of 'em.



Geranium for Pelargonium, and chrysanthemum for Dendrathema are
instances of vernacular names derived from old botanical names; they're
either examples of the first category, or of none of the three
categories.

I would think that Lavatera olbia hort (= Lavatera x clementii) would be
an example of the 3rd category.
--
Stewart Robert Hinsley