Went on another shopping spree yesterday and bought three carry bags full of plants (for less that £6!)
Anyway - among them was a Calla/Arum lily.
The label seems to suggest that it is a tender plant, but the lady at the nursery said it was hardy. So I'm confused? What shall I do with it in the winter? (Fairly sheltered garden in greater London - my neighbour has loads of white ones that survive the winter.)
Can all Callas go in the bog garden? (I've forgotten what type it is!)
It is absolutely gorgeous - deep purple in colour.
I asked a question about Arum lilies recently, here is the link, it may answer your question.
http://www.allotments4all.co.uk/yabbse/index.php?board=2;action=display;threadid=3973 (http://www.allotments4all.co.uk/yabbse/index.php?board=2;action=display;threadid=3973)
Hope it helps :)
It occured to me after my comment there that what you may want to do is plant them with some sand underneath, a la lilies, to aid drainage.
I keep my Callas in a large pot Aqui and take it into the greenhouse to over winter as mine is not a hardy one.