By Steveg1966
West Yorkshire,
United Kingdom 
Zantedeschia sp (Giant spotted Calla Lily) I have this growing and flowering in the greenhouse the tuber is about 8 inch long and lives in a large pot. What I want to do is cut this tuber in half. What is the best way to do this?
6 Dec, 2011
Answers
I wouldn't recommend cutting any rhizome in half...
6 Dec, 2011
That was my thought MG but when I bought the rhizome it was broken in half damaged in the post and I have two plants that have done well.
6 Dec, 2011
Well in that case, if you know it works, do it - but as I said, I'd wait till Spring...
6 Dec, 2011
Each piece would need to have a bud on or it wouldn't have anything to grow from.
6 Dec, 2011
RHS states dividing the rhizomes in late summer?!
6 Dec, 2011
So they might as a general rule but spring is the time for Zantedeschia so they grow on that year.
6 Dec, 2011
Avkg47 is right though - that is the RHS advice, late summer.
6 Dec, 2011
Usual procedure with these is to wait until it grows more 'branches' on its rhizome, then split those off. Not sure about just cutting one in half, maybe someone else knows. Whatever you choose to do, best done in Spring.
6 Dec, 2011