In article , Rod
writes

The candelabra primulas like Fujii, Postford White, Miller's Crimson etc
should do fine where your denticulatas grow well. You won't need to divide
them - if they're happy they will self sow all over the place. If you grow
the Crimson too close to the whites you will get hybrids - some quite nice
pinks, most a bit nondescript.
Some of the species are a bit more choosy about conditions but P. beesiana
and P.bulleyana are worth trying. Don't give up on the P.vialli, I suspect
it's short lived perennnial rather than annual

Yes, it is a short lived perennial.
When I grew them they flowered in their second year from seed and for
another 2-3 years after that. I think it was the winter wet that did for
them.

and a fine plant if it grows
well.

It is indeed. Very dramatic with its two colours, and lasts well. The
sort of plant that attracts lots of queries from passers-by.

Seeds from some sources seem to produce better plants than others -
it's fairly new to me so I'm still learning about it.


--
Kay Easton

Edward's earthworm page:
http://www.scarboro.demon.co.uk/garden/