Nick Maclaren wrote:
Sacha writes:

I realise the accepted wisdom is that Arums like to be very damp
but we have two large clumps at the bottom of our garden which
flower like crazy. It's possibly the driest part of the garden
where the soil can crack wide open in dry weather. It has a
certain amount of shade, though not deep. I think it's not
absolutely essential to plant Arums in damp areas.

It certainly depends on the species. Lords and Ladies grows in
places that dry out in summer, and Crete has several that take
dessicated conditions in summer.

If the OP is talking about the white 'Calla lilies' or Zantedeschia
aethiopica, they seem to thrive in a wide range of conditions. I always
thought I'd never be able to grow it in the open ground but two of my
neighbours have large, well-flowering clumps. One told me she doesn't give
it extra water, except in really droughty conditions, and our soil is very
light and sandy. That's another thing added to my steadily growing 'wants'
list.

Hugh, I'd be inclined to plant the new one out in a suitable spot, keeping
it well watered while it's settling in, and leave the established plant
where it is but give it a protective mulch later in the year if you're in a
cold area.

--
Sue