there are double forms but I dont think they are in the De Caen series. there are several series of these so have a look for St Bridgit etc.

Hi Louise, I can see I got pipped at the post there by Seaburn Girl ... I went off to make a coffee and get my books out came back and found your question answered :)

St Bridgit certainly do produce double and semi double flowers ... it's possible you got a stray bulb in your packet - just like my mystery aliums - meant to be 18" - currently 4 feet! I scowl at them every morning! Hope my mystery plants look as good as yours though :)

This wasn't from a packet of bulbs, it was a pot grown plant bought at a local garden centre, i bought 4 at the same time and this is only happening on 1 plant, could that still happen ?
I've just googled A. coronaria St Bridgit and it looks just like it ..... frilly etc.
However, why are the earlier flowers on this plant the normal flat singles of a de Caen ?

perhaps they potted them up with a stray one in it. and it looks like it is coming from the other corm. If you are really desperate to find out dig the plant up and gently tease them apart to get to the corms. I dont think it is worth risking losing such a pretty plant.

I'll not fiddle with it Seaburn, i'm more than happy for this plant to do its own thing :-)))

:-)